HTML Guides

Bad value “Pragma” for attribute “http-equiv” on element “meta”.

The Pragma HTTP header is a holdover from HTTP/1.0, originally used to instruct proxies and browsers not to cache a response. In older HTML specifications, developers sometimes placed <meta http-equiv="Pragma" content="no-cache"> in their documents, hoping browsers would treat it like a real HTTP header. However, the HTML living standard (maintained by WHATWG) restricts the http-equiv attribute to a small set of recognized values: content-type, default-style, refresh, x-ua-compatible, and content-security-policy. The value Pragma is not among them, which is why the W3C validator flags it as invalid.

Beyond the validation error, this approach has always been unreliable. Browsers and caching proxies generally ignore http-equiv meta tags for cache control purposes — they rely on actual HTTP response headers sent by the server. Keeping this invalid tag in your HTML provides a false sense of security while producing no real caching benefit.

Why this is a problem

Standards compliance: Using an unrecognized http-equiv value produces invalid HTML that fails W3C validation.
No practical effect: Most browsers and all intermediary proxies (CDNs, reverse proxies) ignore cache directives embedded in <meta> tags. Only real HTTP headers reliably control caching behavior.
Misleading code: Developers maintaining the codebase may assume caching is properly managed in HTML when it isn't, leading to unexpected caching issues in production.

How to fix it

Remove the invalid <meta> tag from your HTML <head>.
Configure caching via HTTP response headers on your server. Set Cache-Control (and optionally Pragma for HTTP/1.0 compatibility) as actual headers in your server configuration or application code.

For example, in an Apache .htaccess file:

Header set Cache-Control "no-cache, no-store, must-revalidate"

Header set Pragma "no-cache"

Or in an Nginx configuration:

add_header Cache-Control "no-cache, no-store, must-revalidate";

add_header Pragma "no-cache";

These server-side headers are the correct and effective way to manage caching.

Examples

Incorrect: using `Pragma` in `http-equiv`

This triggers the validation error:

<head>

</head>

Incorrect: using `Cache-Control` in `http-equiv`

While Cache-Control is also sometimes seen in <meta> tags, it is not a valid http-equiv value in the HTML standard either, and browsers largely ignore it:

<head>

</head>

Correct: remove the invalid tag and use server headers

Simply remove the caching meta tag. Your HTML stays clean and valid:

<!DOCTYPE html>

<head>

</head>

<body>

<p>Cache control is handled by server-side HTTP headers.</p>

</body>

</html>

Then configure your web server to send the appropriate Cache-Control and Pragma HTTP response headers as shown in the server configuration examples above. This is the only reliable way to control how browsers and proxies cache your pages.

Bad value “presentation” for attribute “role” on element “img”

The HTML specification defines a specific list of allowed ARIA roles for each element. For the <img> element, role="none" is permitted but role="presentation" is not listed as a valid value. This distinction exists even though the WAI-ARIA 1.1 specification treats none and presentation as synonymous — role="none" was introduced as an alias specifically because the word "presentation" was often misunderstood by authors. The HTML spec adopted none as the canonical value for <img>.

Why this matters

Standards compliance: Using a role value not permitted by the HTML specification for a given element produces a validation error. Keeping your HTML valid ensures predictable behavior across browsers and assistive technologies.

Accessibility: The intended purpose of role="presentation" or role="none" is to tell assistive technologies that an element is purely decorative and carries no semantic meaning. However, for images, the established and most reliable way to achieve this is simply providing an empty alt attribute (alt=""). Screen readers already know to skip images with alt="", so adding a role is usually unnecessary.

Clarity of intent: Using alt="" clearly communicates to both browsers and developers that the image is decorative. If the image actually conveys information, it should have a meaningful alt value and no presentation-related role at all.

How to fix it

If the image is decorative: Remove the role attribute entirely and ensure the image has alt="". This is the simplest and most widely supported approach.
If you need an explicit ARIA role: Replace role="presentation" with role="none" and keep alt="".
If the image conveys meaning: Remove the role and provide a descriptive alt attribute that explains what the image communicates.

Examples

❌ Bad: using `role="presentation"` on an `<img>`

This triggers the validation error because presentation is not an allowed role value for <img> in the HTML specification.

✅ Fixed: decorative image with empty `alt` (preferred)

The empty alt attribute is sufficient to tell assistive technologies the image is decorative. No role is needed.

✅ Fixed: decorative image with `role="none"`

If you explicitly need an ARIA role, role="none" is the valid value for <img>. The empty alt should still be included.

✅ Fixed: meaningful image with descriptive `alt`

If the image communicates information, provide a descriptive alt and do not use a presentation or none role — doing so would hide the image's meaning from assistive technology users.

❌ Bad: meaningful image incorrectly hidden

This is both invalid HTML (wrong role value for <img>) and an accessibility problem — the role would attempt to hide a meaningful image from screen readers.

Bad value “presentation” for attribute “role” on element “video”.

Bad value “presentational” for attribute “role” on element X.

This error occurs when you use role="presentational" on an HTML element. While the intent is clear — you want to strip the element's implicit ARIA semantics — the value presentational does not exist in the WAI-ARIA specification. It's a common typo or misconception. The two valid roles for this purpose are presentation and none, which are synonyms of each other.

When you apply role="presentation" or role="none" to an element, you're telling assistive technologies (like screen readers) to ignore the element's implicit semantic meaning. For example, a <table> used purely for layout purposes has no tabular data semantics, so role="presentation" removes the table-related semantics from the accessibility tree. However, the content inside the element remains accessible — only the container's semantics (and in some cases, its required associated descendants) are removed.

This matters for several reasons:

Standards compliance: Using an invalid role value means the attribute is essentially ignored by browsers and assistive technologies, so the element's semantics are not removed as intended.
Accessibility: If a screen reader encounters an unknown role, it may fall back to the element's default semantics, leading to a confusing experience. For instance, a layout table without a valid presentation role may still be announced as a data table.
Browser consistency: Invalid ARIA values can lead to unpredictable behavior across different browsers and assistive technologies.

To fix this, simply replace presentational with presentation or none.

Examples

❌ Incorrect: using the invalid `presentational` role

<tr>

<td>Column 1</td>

<td>Column 2</td>

</tr>

</table>

✅ Correct: using `presentation`

<tr>

<td>Column 1</td>

<td>Column 2</td>

</tr>

</table>

✅ Correct: using `none` (synonym for `presentation`)

<tr>

<td>Column 1</td>

<td>Column 2</td>

</tr>

</table>

Other elements where this applies

The presentation / none role can be used on various elements, not just tables. Here's another common example with an image used purely for decoration:

When to use `presentation` vs. `none`

Both presentation and none are functionally identical. The none role was introduced later as a clearer name, since presentation can be confused with visual presentation. For maximum browser support, some developers use both:

<tr>

<td>Layout content</td>

</tr>

</table>

This fallback pattern ensures that older assistive technologies that don't recognize none will still pick up presentation. However, in most modern environments, either value alone is sufficient.

Bad value “rocketlazyloadscript” for attribute “type” on element “script”: Subtype missing.

script
type

Understanding the Issue

MIME types follow a specific format: a type and a subtype separated by a forward slash, such as text/javascript or application/json. When the W3C validator encounters type="rocketlazyloadscript" on a <script> element, it flags it because this value has no slash and no subtype — it doesn't conform to the MIME type syntax defined in the HTML specification.

The value rocketlazyloadscript is intentionally set by the WP Rocket WordPress caching and performance plugin. WP Rocket changes the type attribute of <script> elements from text/javascript (or removes the default) and replaces it with this custom value. This prevents the browser from executing the script immediately on page load. WP Rocket's JavaScript then swaps the type back to a valid value when the script should actually be loaded, achieving a lazy-loading effect that can improve page performance.

Why This Is Flagged

The HTML specification states that if the type attribute is present on a <script> element, its value must be one of the following:

A valid JavaScript MIME type (e.g., text/javascript) — indicating the script should be executed.
The string module — indicating the script is a JavaScript module.
Any other valid MIME type that is not a JavaScript MIME type — indicating a data block that the browser should not execute.

Since rocketlazyloadscript is not a valid MIME type at all (it lacks the type/subtype structure), it fails validation. While browsers will simply ignore scripts with unrecognized type values (which is exactly what WP Rocket relies on), the markup itself is technically non-conforming.

How to Fix It

Because this value is generated by a plugin rather than authored manually, your options are:

Configure WP Rocket to exclude specific scripts — In WP Rocket's settings under "File Optimization," you can exclude individual scripts from the "Delay JavaScript execution" feature. This prevents WP Rocket from modifying their type attribute.
Disable delayed JavaScript execution entirely — If W3C compliance is critical, you can turn off the "Delay JavaScript execution" option in WP Rocket. This eliminates the validation errors but sacrifices the performance benefit.
Accept the validation errors — WP Rocket acknowledges these errors in their documentation and considers them an expected side effect of their optimization technique. Since browsers handle the non-standard type gracefully (by not executing the script), there is no functional or accessibility issue. The errors are purely a standards compliance concern.

Examples

Invalid: Non-standard type value (generated by WP Rocket)

The validator reports: Bad value "rocketlazyloadscript" for attribute "type" on element "script": Subtype missing.

Valid: Standard type attribute

Valid: Omitting the type attribute entirely

Since text/javascript is the default for <script> elements in HTML5, the type attribute can be omitted entirely:

Valid: Using a module script

Valid: Using a data block with a proper MIME type

If you need a non-executed data block, use a valid MIME type that isn't a JavaScript type:

{"lazy": true, "threshold": 200}

</script>

Bad value “rowgroup” for attribute “role” on element “header”.

The rowgroup role represents a group of rows within a tabular structure — similar to what <thead>, <tbody>, or <tfoot> provide in a native HTML <table>. According to the ARIA specification, the rowgroup role should be used on elements that serve as structural containers for rows within a grid, table, or treegrid. A <header> element is not appropriate for this role because it carries its own strong semantic meaning (typically banner or a sectioning header), and overriding it with role="rowgroup" creates a conflict that the W3C validator flags.

This matters for several reasons. First, assistive technologies rely on correct role assignments to convey the structure of a page. When a <header> element is given role="rowgroup", screen readers receive contradictory signals about what the element represents, which can confuse users. Second, the HTML specification restricts which ARIA roles can be applied to certain elements — the <header> element does not allow rowgroup as a valid role override.

To fix this issue, you have two main options:

Replace the <header> element with a <div> — since <div> has no implicit ARIA role, it freely accepts role="rowgroup".
Use native HTML table elements — replace the custom ARIA table structure with <table>, <thead>, <tbody>, <tr>, <th>, and <td>, which provide the correct semantics without requiring any ARIA roles.

Examples

❌ Incorrect: `role="rowgroup"` on a `<header>` element

<span role="columnheader">Quarter</span>

<span role="columnheader">Revenue</span>

</div>

</header>

</div>

The validator reports Bad value "rowgroup" for attribute "role" on element "header" because <header> cannot accept the rowgroup role.

✅ Fix option 1: Use a `<div>` instead of `<header>`

<span role="columnheader">Quarter</span>

<span role="columnheader">Revenue</span>

</div>

</div>

A <div> is semantically neutral, so role="rowgroup" is perfectly valid on it.

✅ Fix option 2: Use native HTML table elements

<table>

<caption>Quarterly Sales</caption>

<thead>

<tr>

<th>Quarter</th>

<th>Revenue</th>

</tr>

</thead>

<tbody>

<tr>

</tr>

</tbody>

</table>

Native table elements like <thead> and <tbody> implicitly carry the rowgroup role, so no ARIA attributes are needed at all. This approach is generally preferred because it provides the best accessibility support out of the box and results in cleaner, more maintainable markup. Only use ARIA table roles when you cannot use native HTML tables (for example, when building a custom grid layout that requires non-table CSS).

Bad value “screen,projection” for attribute “media” on element “link”: The media “projection” has been deprecated

Media types describe the general category of a device for which a stylesheet is intended. The most commonly used values are screen (for computer screens, tablets, and phones), print (for print preview and printed pages), and all (the default, for all devices).

Understanding Deprecated Media Types

CSS 2.1 and Media Queries 3 defined several additional media types: tty, tv, projection, handheld, braille, embossed, and aural. All of these were deprecated in the Media Queries 4 specification. The projection type was originally intended for projected presentations (such as slideshows), but modern browsers never meaningfully distinguished between screen and projection rendering contexts.

Why This Is a Problem

Standards compliance: Using deprecated media types produces validator warnings and means your code doesn't conform to current web standards.
No practical effect: Modern browsers treat unrecognized or deprecated media types as not matching, which means a stylesheet targeted only at projection would never be applied. When combined with screen in a comma-separated list (e.g., screen,projection), the projection portion is simply ignored — it adds clutter without benefit.
Maintainability: Keeping deprecated values in your markup can confuse other developers and suggest that the code targets a platform that no longer exists in the spec.

How to Fix It

Remove the deprecated media type from the media attribute, keeping only valid types like screen, print, speech, or all.
Remove the media attribute entirely if the remaining value is all or if you only need screen (since screen is the most common rendering context and stylesheets without a media attribute default to all).
Use modern media features instead of deprecated media types if you need to target specific device capabilities (e.g., (hover: none), (pointer: coarse), (display-mode: fullscreen)).

Examples

❌ Incorrect: Using the deprecated `projection` media type

This triggers the validation warning because projection has been deprecated.

✅ Correct: Using only the `screen` media type

✅ Correct: Removing the `media` attribute entirely

If you want the stylesheet to apply to all media types (the default behavior), simply omit the attribute:

✅ Correct: Combining valid media types

If you need your stylesheet to apply to both screen and print contexts:

❌ Other deprecated media types to avoid

All of the following are deprecated and will produce similar warnings:

Replace these with screen, print, speech, all, or use specific media features to target the device characteristics you need.

Bad value “search” for attribute “role” on element “input”.

The search ARIA role is a landmark role, which means it identifies a large, navigable section of a page — specifically, the region that contains the search functionality. Landmark roles help assistive technologies (like screen readers) quickly identify and jump to major sections of a document. Because landmarks describe sections of a page, they belong on container elements that encompass all the parts of the search interface (the label, the input field, the submit button, etc.), not on a single <input> element.

When you place role="search" on an <input>, the validator rejects it because the search role doesn't match the semantics of an input control. An <input> represents a single interactive widget, not a page region. The valid way to indicate that an input field is for search queries is to use <input type="search">, which gives browsers and assistive technologies the correct semantic meaning for that specific control.

Meanwhile, if you want to mark an entire search form as a search landmark, apply role="search" to the <form> element that wraps the search controls. In modern HTML, you can also use the <search> element, which has the implicit search landmark role without needing any ARIA attribute.

How to fix it

Remove role="search" from the <input> element.
Change the input's type to "search" — this tells browsers and assistive technologies that the field is for search queries.
Apply role="search" to the wrapping <form>, or use the HTML <search> element as the container.

Examples

❌ Incorrect: `role="search"` on an `<input>`

<form>

<label for="query">Search</label>

</form>

This triggers the validation error because search is not a valid role for <input>.

✅ Correct: `type="search"` on the input, `role="search"` on the form

<label for="query">Search this site</label>

</form>

Here, role="search" is correctly placed on the <form> element, creating a search landmark. The <input type="search"> conveys the correct semantics for the input field itself.

✅ Correct: Using the `<search>` element (modern HTML)

<form>

<label for="query">Search this site</label>

</form>

</search>

The <search> element has the implicit ARIA role of search, so no explicit role attribute is needed on either the container or the form. This is the most semantic approach in browsers that support it.

✅ Correct: Standalone search input without a landmark

If you simply need a search-styled input without marking up a full landmark region, just use type="search":

<label for="filter">Filter results</label>

This gives the input the correct semantics and allows browsers to provide search-specific UI features (such as a clear button) without requiring a landmark role.

Bad value “section” for attribute “role” on element “section”.

The value section does not exist in the WAI-ARIA specification. ARIA defines a specific set of role values, and section is not among them. This is likely a confusion between the HTML element name <section> and the ARIA role region, which is the role that the <section> element implicitly maps to. Because section is not a recognized role, the validator rejects it as an invalid value.

This matters for several reasons. First, assistive technologies like screen readers rely on ARIA roles to communicate the purpose of elements to users. An unrecognized role value may be ignored entirely or cause unexpected behavior, degrading the experience for users who depend on these tools. Second, the <section> element already carries native semantics equivalent to role="region" (when it has an accessible name), so adding a redundant or incorrect role provides no benefit and introduces potential problems.

According to the ARIA in HTML specification, you should generally avoid setting a role on elements that already have appropriate native semantics. The <section> element's implicit role is region, so explicitly adding role="region" is redundant in most cases. The simplest and best fix is to remove the role attribute altogether and let the native HTML semantics do their job.

If you do need to override an element's role for a specific design pattern (for example, turning a <section> into a navigation landmark), use a valid ARIA role from the WAI-ARIA specification.

Examples

Incorrect: using the invalid `section` role

<h2>About Us</h2>

<p>Learn more about our team.</p>

</section>

This triggers the validation error because section is not a valid ARIA role value.

Correct: remove the role attribute

<h2>About Us</h2>

<p>Learn more about our team.</p>

</section>

The <section> element already provides the correct semantics. No role attribute is needed.

Correct: use a valid ARIA role if needed

If you have a specific reason to assign a role, use a valid one. For example, if a <section> is being used as a navigation landmark:

<ul>

<li><a href="/about">About</a></li>

</ul>

</section>

In practice, you would typically use a <nav> element instead, which has the navigation role natively. This example simply illustrates that if you do apply a role, it must be a valid ARIA role value.

Correct: explicit `region` role with an accessible name

If you want to explicitly mark a section as a named region landmark, you can use role="region" along with an accessible name. However, this is redundant when using <section> with an aria-label or aria-labelledby, since the browser already maps it to region:

<h2 id="features-heading">Features</h2>

<p>Explore our product features.</p>

</section>

<h2 id="features-heading">Features</h2>

<p>Explore our product features.</p>

</section>

Both are valid HTML, but the first approach is cleaner and follows the principle of relying on native semantics whenever possible.

Bad value “sidebar” for attribute “role” on element “div”.

ARIA defines a closed set of role tokens. Browsers and assistive technologies rely on this fixed list to determine how an element should be announced and how it fits into the page's landmark structure. When a role value falls outside that list, the attribute is effectively ignored. A screen reader encountering role="sidebar" will not recognize the element as a landmark, so users who navigate by landmarks will skip right past it. Automated accessibility testing tools will also flag it as an error, and the validator will reject it outright.

The concept most people mean when they write role="sidebar" is ancillary or tangential content related to the main content of the page. ARIA calls this the complementary role. In semantic HTML, the <aside> element maps to complementary without any explicit role attribute. Using <aside> is the simplest fix and keeps the markup clean.

A few things to keep in mind when choosing the replacement:

If the sidebar contains related content, promotional links, or supplementary information, complementary (via <aside> or role="complementary") is correct.
If the sidebar is actually a set of navigation links, use <nav> or role="navigation" instead. Pick the role that matches the content's purpose, not its visual position.
When a page has more than one complementary region, each one needs a distinct accessible name so screen reader users can tell them apart. Use aria-labelledby pointing to a visible heading, or aria-label if no heading is present.
Do not add role="complementary" to an <aside> element. The implicit mapping already handles it, and the redundant attribute adds noise without benefit.

Examples

Invalid: non-existent ARIA role

This triggers the validator error because sidebar is not a defined ARIA role.

<h2>Related links</h2>

<ul>

<li><a href="/guide-a">Guide A</a></li>

<li><a href="/guide-b">Guide B</a></li>

</ul>

</div>

Fixed: use `role="complementary"` on a generic container

If you need to keep the <div>, assign the correct ARIA role and provide an accessible name.

<h2 id="sidebar-title">Related links</h2>

<ul>

<li><a href="/guide-a">Guide A</a></li>

<li><a href="/guide-b">Guide B</a></li>

</ul>

</div>

Fixed: use `<aside>` for semantic HTML

The <aside> element has an implicit complementary role, so no role attribute is needed.

<h2 id="sidebar-title">Related links</h2>

<ul>

<li><a href="/guide-a">Guide A</a></li>

<li><a href="/guide-b">Guide B</a></li>

</ul>

</aside>

Multiple complementary regions with distinct labels

When a page has more than one <aside>, give each a unique accessible name so users can distinguish them.

<h2 id="filters-title">Filter results</h2>

</aside>

<h2 id="related-title">Related articles</h2>

</aside>

When the content is navigation, not complementary

A sidebar that contains section links or site links is navigation, not complementary content. Use <nav> instead.

<ul>

<li><a href="#intro">Intro</a></li>

<li><a href="#examples">Examples</a></li>

<li><a href="#contact">Contact</a></li>

</ul>

</nav>

Valid ARIA landmark roles

For reference, these are the ARIA landmark roles that browsers and assistive technologies recognize:

banner (implicit on <header> when not nested inside a sectioning element)
navigation (implicit on <nav>)
main (implicit on <main>)
complementary (implicit on <aside>)
contentinfo (implicit on <footer> when not nested inside a sectioning element)
region (implicit on <section> when it has an accessible name)
search (implicit on <search>)
form (implicit on <form> when it has an accessible name)

Stick to these defined values. Inventing role names like sidebar, content, or wrapper will always produce a validation error and provide no accessibility benefit.

Bad value “sidebar” for attribute “role” on element “span”.

ARIA defines a fixed set of role values that user agents and assistive technologies understand. sidebar is not in that set, so role="sidebar" fails conformance checking and gives unreliable signals to screen readers. Using a valid role or the correct HTML element improves accessibility, ensures consistent behavior across browsers and AT, and keeps your markup standards‑compliant.

Sidebars typically contain tangential or ancillary content (e.g., related links, promos, author info). The ARIA role that matches that meaning is complementary. In HTML, the semantic element for the same concept is aside, which by default maps to the complementary landmark in accessibility APIs. Prefer native semantics first: use <aside> when possible. Only add role="complementary" when you can’t change the element type or when you need an explicit landmark for non-semantic containers.

How to fix:

If the element is a sidebar: change <div role="sidebar"> to <aside> (preferred), or to <div role="complementary">.
Ensure each page has at most one primary main region and that complementary regions are not essential to understanding the main content.
Provide an accessible name for the complementary region when multiple exist, using aria-label or aria-labelledby, to help users navigate landmarks.

Examples

Triggers the validator error

</div>

Fixed: use the semantic element (preferred)

</aside>

Fixed: keep the container, apply a valid role

</div>

Full document example with two sidebars (each labeled)

<!doctype html>

<head>

<title>Sidebar Landmarks Example</title>

</head>

<body>

<h1>News Today</h1>

</header>

<h2>Main Story</h2>

</article>

</main>

<ul>

<li>Science</li>

<li>Politics</li>

<li>Sports</li>

</ul>

</aside>

<h2 id="sponsor-title">Sponsored</h2>

<p>Ad content</p>

</div>

</footer>

</body>

</html>

Notes:

Do not invent ARIA roles (e.g., sidebar, hero, footer-nav). Use defined roles like complementary, navigation, banner, contentinfo, and main.
Prefer native HTML elements (aside, nav, header, footer, main) over generic containers with roles.
Label multiple complementary landmarks to make them distinguishable in screen reader landmark lists.

Bad value “street-address” for attribute “autocomplete” on element “input”: The autofill field name “street-address” is not allowed in this context.

The HTML specification defines specific rules about which autocomplete values can be used on which form elements. The street-address token is categorized as a "multiline" autofill field because street addresses often span multiple lines (e.g., "123 Main St\nApt 4B"). Since <input> elements only accept single-line text, the spec prohibits using street-address with them. The <textarea> element, on the other hand, naturally supports multiline content, making it the appropriate host for this token.

This matters for several reasons. First, browsers use autocomplete values to offer autofill suggestions. When the element type doesn't match the expected data format, browsers may not autofill correctly or may ignore the hint entirely. Second, standards compliance ensures consistent behavior across different browsers and assistive technologies. Third, using the correct pairing improves the user experience — users expect their full street address to appear in a field that can actually display it properly.

You have two approaches to fix this:

Use a <textarea> — If you want the full street address in a single field, switch from <input> to <textarea>. This is the most semantically correct choice when you expect multiline address data.
Use line-specific tokens on <input> elements — If your form design uses separate single-line fields for each part of the address, use address-line1, address-line2, and address-line3 instead. These tokens are explicitly allowed on <input> elements.

Examples

❌ Invalid: `street-address` on an `<input>`

<label for="address">Street Address</label>

This triggers the validation error because street-address requires a multiline control.

✅ Fix: Use a `<textarea>` with `street-address`

<label for="address">Street Address</label>

The <textarea> supports multiline text, so street-address is valid here.

✅ Fix: Use line-specific tokens on `<input>` elements

<label for="address1">Address Line 1</label>

<label for="address2">Address Line 2</label>

The address-line1, address-line2, and address-line3 tokens are single-line autofill fields and are perfectly valid on <input> elements. This approach is common in forms that break the address into separate fields for apartment numbers, building names, or other details.

Summary of allowed pairings

Token	`<input>`	`<textarea>`
`street-address`	❌ Not allowed	✅ Allowed
`address-line1`	✅ Allowed	✅ Allowed
`address-line2`	✅ Allowed	✅ Allowed
`address-line3`	✅ Allowed	✅ Allowed

Choose the approach that best fits your form layout. If you prefer a single address field, use <textarea> with street-address. If you prefer structured, separate fields, use <input> elements with the appropriate address-line tokens.

Bad value “tabpanel” for attribute “role” on element “article”.

The article element has an implicit ARIA role of article, which signals to assistive technologies that it contains a self-contained, independently distributable piece of content—like a blog post, news story, or forum entry. When you add role="tabpanel" to an article, you're attempting to override this strong semantic meaning with a widget role, which the HTML specification does not permit. The ARIA in HTML specification defines a strict set of allowed roles for each HTML element, and tabpanel is not in the list of permissible roles for article.

This matters for several reasons. First, assistive technologies like screen readers rely on accurate role information to communicate the purpose of elements to users. An article element claiming to be a tabpanel creates a confusing and contradictory signal. Second, the W3C validator flags this as an error, meaning your markup is technically invalid. Third, browsers may handle this conflict inconsistently—some might honor the explicit role, while others might prioritize the element's native semantics, leading to unpredictable behavior across platforms.

The tabpanel role is designed for use in a tab interface pattern alongside role="tablist" and role="tab". According to the WAI-ARIA Authoring Practices, a tab panel should be a generic container that holds the content associated with a tab. Elements like div and section are ideal because they don't carry conflicting implicit roles (div has no implicit role, and section maps to region only when given an accessible name, which gets properly overridden by tabpanel).

To fix the issue, simply change the article element to a div or section. If you genuinely need the semantic meaning of article within a tab panel, nest the article inside the div that carries the tabpanel role.

Examples

Incorrect: `tabpanel` role on an `article` element

<h2>Latest News</h2>

<p>Tab panel content here.</p>

</article>

This triggers the validation error because article does not allow the tabpanel role.

Correct: `tabpanel` role on a `div`

<h2>Latest News</h2>

<p>Tab panel content here.</p>

</div>

Correct: Nesting an `article` inside the tab panel

If you need the article semantics for the content within the panel, nest it:

<h2>Latest News</h2>

<p>This is a self-contained article displayed within a tab panel.</p>

</article>

</div>

Full tab interface example

Here's a complete, valid tab interface implementation:

<!DOCTYPE html>

<head>

<title>Tab Interface Example</title>

</head>

<body>

<button role="tab" id="tab2" aria-controls="panel2" aria-selected="false">Sports</button>

</div>

<p>Latest news content goes here.</p>

</div>

<p>Sports content goes here.</p>

</div>

</body>

</html>

Note the use of aria-controls on each tab to reference its corresponding panel, aria-labelledby on each tabpanel to reference its controlling tab, and the hidden attribute on inactive panels. These associations ensure assistive technologies can properly navigate the tab interface.

Bad value “tabpanel” for attribute “role” on element “ul”.

The W3C validator raises this error because ARIA roles must be compatible with the element they are applied to. A <ul> element has an implicit ARIA role of list, and overriding it with tabpanel creates a conflict. The tabpanel role signals to assistive technologies that the element is a panel of content activated by a corresponding tab. When this role is placed on a <ul>, screen readers lose the semantic meaning of the list (item count, list navigation, etc.) while also misrepresenting the element's function in the tab interface.

This matters for several reasons:

Accessibility: Screen reader users rely on correct roles to navigate and understand page structure. A <ul> marked as tabpanel confuses both its list semantics and its role in the tab interface.
Standards compliance: The ARIA in HTML specification defines which roles are allowed on which elements. The tabpanel role is not permitted on <ul>.
Browser behavior: Browsers may handle conflicting roles inconsistently, leading to unpredictable behavior across assistive technologies.

The fix is straightforward: wrap the <ul> inside a proper container element (like a <div> or <section>) and apply the tabpanel role to that container instead.

Examples

Incorrect: `tabpanel` role on a `<ul>`

This triggers the validation error because tabpanel is not a valid role for <ul>:

<button role="tab" aria-controls="panel-1" aria-selected="true" id="tab-1">Appetizers</button>

<button role="tab" aria-controls="panel-2" aria-selected="false" id="tab-2">Desserts</button>

</div>

<li>Bruschetta</li>

<li>Spring rolls</li>

</ul>

<li>Tiramisu</li>

<li>Cheesecake</li>

</ul>

Correct: `tabpanel` role on a container wrapping the `<ul>`

Move the tabpanel role to a <div> and nest the <ul> inside it. This preserves both the tab panel semantics and the list semantics:

<button role="tab" aria-controls="panel-1" aria-selected="true" id="tab-1">Appetizers</button>

<button role="tab" aria-controls="panel-2" aria-selected="false" id="tab-2">Desserts</button>

</div>

<ul>

<li>Bruschetta</li>

<li>Spring rolls</li>

</ul>

</div>

<ul>

<li>Tiramisu</li>

<li>Cheesecake</li>

</ul>

</div>

Correct: Using `<section>` as the tab panel

A <section> element also works well as a tab panel container, especially when the panel content is more complex:

<button role="tab" aria-controls="tasks-panel" aria-selected="true" id="tasks-tab">Tasks</button>

<button role="tab" aria-controls="notes-panel" aria-selected="false" id="notes-tab">Notes</button>

</div>

<h2>Current tasks</h2>

<ul>

<li>Review pull requests</li>

<li>Update documentation</li>

</ul>

</section>

<h2>Meeting notes</h2>

<p>Discussed project timeline and milestones.</p>

</section>

In a properly structured tabbed interface:

The tablist role goes on the container that holds the tab buttons.
Each tab trigger gets role="tab" with aria-controls pointing to its panel's id.
Each content panel gets role="tabpanel" on a generic container like <div> or <section>, with aria-labelledby referencing the corresponding tab's id.
List elements like <ul> and <ol> should remain inside the panel as regular content, retaining their native list semantics.

Bad value “tel-national” for attribute “autocomplete” on element “input”: The autofill field name “tel-national” is not allowed in this context.

The HTML specification defines specific rules about which autocomplete autofill field names can be paired with which input types. The tel-national token (which represents a phone number without the country code) is classified as requiring a text-based input control. Meanwhile, <input type="tel"> is a specialized control that the spec treats differently from a plain text field. When the validator encounters tel-national on a type="tel" input, it flags the mismatch because the autofill field name is not allowed in that context.

This might seem counterintuitive — a national telephone number value on a telephone input feels like a natural fit. However, the distinction exists because type="tel" already implies a complete telephone number, and the spec maps the broader tel autocomplete token to it. The more granular telephone tokens like tel-national, tel-country-code, tel-area-code, tel-local, tel-local-prefix, and tel-local-suffix are designed for type="text" inputs where a phone number is being broken into individual parts across multiple fields.

Getting this right matters for browser autofill behavior. When the autocomplete value and input type are properly paired according to the spec, browsers can more reliably populate the field with the correct portion of the user's stored phone number. An invalid pairing may cause autofill to silently fail or behave unpredictably across different browsers.

How to fix it

You have two options:

Change the input type to text — Use type="text" if you specifically want the national portion of a phone number (without the country code). This is the right choice when you're splitting a phone number across multiple fields.
Change the autocomplete value to tel — Use autocomplete="tel" if you want a single field for the full phone number. This pairs correctly with type="tel".

Examples

❌ Invalid: `tel-national` on `type="tel"`

<label for="phone">Phone number</label>

This triggers the validation error because tel-national is not allowed on a type="tel" input.

✅ Fix option 1: Change input type to `text`

<label for="phone">Phone number (without country code)</label>

Using type="text" satisfies the spec's requirement for the tel-national autofill token. This is ideal when collecting just the national portion of a number.

✅ Fix option 2: Change autocomplete to `tel`

<label for="phone">Phone number</label>

Using autocomplete="tel" is the correct pairing for type="tel" and tells the browser to autofill the complete phone number.

✅ Splitting a phone number across multiple fields

When you need separate fields for different parts of a phone number, use type="text" with the granular autocomplete tokens:

<legend>Phone number</legend>

<label for="country-code">Country code</label>

<label for="national">National number</label>

</fieldset>

Bad value “tel: X” for attribute “href” on element “a”: Illegal character in scheme data.

tel
href

A URI (Uniform Resource Identifier) follows a strict syntax defined by RFC 3986. The general structure is scheme:scheme-data, where no spaces or other illegal characters are allowed between the colon and the scheme-specific data. When the W3C validator reports "Illegal character in scheme data," it means the parser found a character that isn't permitted in that position of the URI.

The most common cause of this error is adding a space after the colon in tel: links (e.g., tel: +123456789). While browsers may be forgiving and still handle the link, the markup is technically invalid. This matters for several reasons:

Accessibility: Screen readers and assistive technologies rely on well-formed URIs to correctly identify link types. A malformed tel: link might not be announced as a phone number.
Standards compliance: Invalid URIs violate the HTML specification, which requires the href attribute to contain a valid URL.
Cross-device behavior: Mobile devices use the URI scheme to determine which app should handle a link. A malformed tel: URI may fail to trigger the phone dialer on some devices or operating systems.
Interoperability: While some browsers silently trim spaces, others may encode them as %20, potentially breaking the phone number or other scheme data.

To fix this issue, ensure there are no spaces or other illegal characters between the scheme's colon and the data that follows it. For telephone links specifically, the number should follow the colon directly, using only digits, hyphens, dots, parentheses, and the + prefix as defined by RFC 3966.

Examples

Incorrect: space after the colon in a `tel:` link

The space between tel: and +1 is an illegal character in the URI scheme data.

Correct: no space after the colon

Incorrect: space after the colon in a `mailto:` link

<a href="mailto: support@example.com">Email support</a>

Correct: `mailto:` with no space

<a href="mailto:support@example.com">Email support</a>

Incorrect: other illegal characters in scheme data

Spaces within the phone number itself are also illegal characters in the URI. Use hyphens, dots, or no separators instead.

Correct: valid separators in a phone number

Visual formatting vs. the `href` value

If you want the displayed phone number to include spaces for readability, format the visible text separately from the href value:

The href contains a valid URI with no spaces, while the link text is formatted for easy reading. This gives you the best of both worlds — valid markup and a user-friendly display.

Bad value “telephone” for attribute “autocomplete” on element “input”: The string “telephone” is not a valid autofill field name.

Bad value “text” for attribute “role” on element “span”.

Bad value “text/html; charset=iso-8859-15” for attribute “content” on element “meta”: “charset=” must be followed by “utf-8”.

Bad value “text/html; charset=Shift_JIS” for attribute “content” on element “meta”: “charset=” must be followed by “utf-8”.

Bad value “text/html; charset=windows-1251” for attribute “content” on element “meta”: “charset=” must be followed by “utf-8”.

The HTML5 specification mandates UTF-8 as the only permitted character encoding for web documents declared via <meta> tags. Legacy encodings such as windows-1251 (a Cyrillic character encoding), iso-8859-1, shift_jis, and others are no longer valid values in HTML5 <meta> declarations. This restriction exists because UTF-8 is a universal encoding that can represent virtually every character from every writing system, eliminating the interoperability problems that plagued the web when dozens of competing encodings were in use.

When the validator encounters content="text/html; charset=windows-1251" on a <meta> element, it flags it because the charset= portion must be followed by utf-8 — no other value is accepted. This applies whether you use the longer <meta http-equiv="Content-Type"> syntax or the shorter <meta charset> syntax.

Why this matters

Standards compliance: The WHATWG HTML Living Standard explicitly requires utf-8 as the character encoding when declared in a <meta> tag. Non-conforming encodings will trigger validation errors.
Internationalization: UTF-8 supports all Unicode characters, making your pages work correctly for users across all languages, including Cyrillic text that windows-1251 was originally designed for.
Security: Legacy encodings can introduce security vulnerabilities, including certain cross-site scripting (XSS) attack vectors that exploit encoding ambiguity.
Browser consistency: While browsers may still recognize legacy encodings, relying on them can cause mojibake (garbled text) when there's a mismatch between the declared and actual encoding.

How to fix it

Update the <meta> tag to declare utf-8 as the charset.
Re-save your file in UTF-8 encoding using your text editor or IDE. Most modern editors support this — look for an encoding option in "Save As" or in the status bar.
Verify your server configuration. If your server sends a Content-Type HTTP header with a different encoding, the server header takes precedence over the <meta> tag. Make sure both agree on UTF-8.
Convert your content. If your text was originally written in windows-1251, you may need to convert it to UTF-8. Tools like iconv on the command line can help: iconv -f WINDOWS-1251 -t UTF-8 input.html > output.html.

Examples

❌ Incorrect: Using `windows-1251` charset

✅ Correct: Using `utf-8` with `http-equiv` syntax

✅ Correct: Using the shorter `<meta charset>` syntax (preferred in HTML5)

Full document example

<!DOCTYPE html>

<head>

<title>Пример страницы</title>

</head>

<body>

<p>Текст на русском языке в кодировке UTF-8.</p>

</body>

</html>

The shorter <meta charset="utf-8"> syntax is generally preferred in HTML5 documents because it's more concise and achieves the same result. Whichever syntax you choose, place the charset declaration within the first 1024 bytes of your document — ideally as the very first element inside <head> — so browsers can detect the encoding as early as possible.

Bad value “text/html; charset=windows-1252” for attribute “content” on element “meta”: “charset=” must be followed by “utf-8”.

The HTML specification mandates that documents must be encoded in UTF-8. This requirement exists because UTF-8 is the universal character encoding that supports virtually every character from every writing system in the world. Older encodings like windows-1252, iso-8859-1, or shift_jis only support a limited subset of characters and can cause text to display incorrectly — showing garbled characters or question marks — especially for users in different locales or when content includes special symbols, accented letters, or emoji.

When the validator encounters charset=windows-1252 in your <meta> tag, it flags this as an error because the HTML living standard (WHATWG) explicitly states that the character encoding declaration must specify utf-8 as the encoding. This isn't just a stylistic preference — browsers and other tools rely on this declaration to correctly interpret the bytes in your document. Using a non-UTF-8 encoding can lead to security vulnerabilities (such as encoding-based XSS attacks) and accessibility issues when assistive technologies misinterpret characters.

To fix this issue, take two steps:

Update the <meta> tag to declare utf-8 as the charset.
Re-save your file with UTF-8 encoding. Most modern code editors (VS Code, Sublime Text, etc.) let you choose the encoding when saving — look for an option like "Save with Encoding" or check the status bar for the current encoding. If your file was originally in windows-1252, simply changing the <meta> tag without re-encoding the file could cause existing special characters to display incorrectly.

The HTML spec also recommends using the shorter <meta charset="utf-8"> form rather than the longer <meta http-equiv="Content-Type" ...> pragma directive, as it's simpler and achieves the same result. Either form is valid, but the charset declaration must appear within the first 1024 bytes of the document.

Examples

Incorrect: Using `windows-1252` charset

This triggers the validator error because the charset is not utf-8.

Correct: Using the short `charset` declaration (recommended)

Correct: Using the `http-equiv` pragma directive with `utf-8`

Full document example

<!DOCTYPE html>

<head>

</head>

<body>

<p>Hello, world!</p>

</body>

</html>

Note that the <meta charset="utf-8"> tag should be the first element inside <head>, before any other elements (including <title>), so the browser knows the encoding before it starts parsing the rest of the document.

Bad value “textbox” for attribute “role” on element “li”.

The textbox ARIA role identifies an element that allows free-form text input. While it can technically be applied to elements using contenteditable, it should not be placed on elements that already carry strong semantic meaning, such as <li>. A list item is expected to be a child of <ul>, <ol>, or <menu>, and its implicit listitem role communicates its purpose within a list structure to assistive technologies. Assigning role="textbox" to an <li> overrides this semantic, confusing screen readers and other assistive tools about whether the element is a list item or a text input field.

This is problematic for several reasons:

Accessibility: Screen readers rely on roles to convey the purpose of elements to users. An <li> with role="textbox" sends mixed signals — it exists within a list structure but announces itself as a text input.
Standards compliance: The ARIA in HTML specification restricts which roles can be applied to specific elements. The li element does not allow the textbox role, which is why the W3C validator flags this as an error.
Browser behavior: Browsers may handle the conflicting semantics unpredictably, leading to inconsistent experiences across different user agents.

The best approach is to use native HTML form elements whenever possible. The <input type="text"> element handles single-line text input, and the <textarea> element handles multi-line input. These native elements come with built-in keyboard support, focus management, and form submission behavior — none of which you get for free with a role="textbox" on a non-form element.

If you genuinely need an editable area inside a list and cannot use native form elements, nest a <div> or <span> with role="textbox" inside the <li> rather than placing the role on the <li> itself.

Examples

❌ Incorrect: `role="textbox"` on an `li` element

<ul>

</ul>

This triggers the validator error because textbox is not a valid role for <li>.

✅ Fix: Use native form elements

The simplest and most robust fix is to use standard form controls:

<ul>

<li>

</li>

<li>

</li>

</ul>

For multi-line input, use <textarea>:

<ul>

<li>

<textarea id="note1">Edit this content</textarea>

</li>

</ul>

✅ Fix: Nest a `div` with `role="textbox"` inside the `li`

If you need a contenteditable area and cannot use native form elements, place the textbox role on a nested element:

<ul>

<li>

<div

role="textbox"

contenteditable="true"

aria-labelledby="label1"

aria-placeholder="Enter text">

Edit this item

</div>

</li>

</ul>

This preserves the <li> element's implicit listitem role while correctly assigning the textbox role to a semantically neutral <div>.

✅ Fix: Remove the list structure entirely

If the items aren't truly a list, consider dropping the <ul>/<li> structure altogether:

<div id="zipLabel">Enter your five-digit zipcode</div>

<div

role="textbox"

contenteditable="true"

aria-placeholder="5-digit zipcode"

aria-labelledby="zipLabel">

</div>

In every case, prefer native <input> and <textarea> elements over role="textbox" with contenteditable. Native elements provide accessible behavior by default, including keyboard interaction, form validation, and proper focus management, without requiring additional ARIA attributes or JavaScript.

Bad value “title” for attribute “http-equiv” on element “meta”.

Bad value “true” for attribute “allowfullscreen” on element “iframe”.

In HTML, boolean attributes like allowfullscreen, disabled, readonly, and hidden work differently from what many developers expect. Their presence alone on an element means "true," and their absence means "false." The only valid values for a boolean attribute are the empty string ("") or the attribute's own name (e.g., allowfullscreen="allowfullscreen"). Setting a boolean attribute to "true" is not valid HTML according to the WHATWG HTML living standard, even though browsers will typically still interpret it as enabled.

This matters for several reasons. First, it violates the HTML specification and will produce a W3C validation error. Second, it can create confusion for other developers who may assume that setting the attribute to "false" would disable it — but that's not how boolean attributes work. Setting allowfullscreen="false" would still enable fullscreen because the attribute is present. Keeping your markup valid and semantically correct avoids these misunderstandings and ensures forward compatibility with browsers and tooling.

It's also worth noting that allowfullscreen is now considered a legacy attribute. The modern approach is to use the allow attribute with the "fullscreen" permission token, which is part of the broader Permissions Policy mechanism. The allow attribute gives you fine-grained control over multiple features in a single attribute.

Examples

Incorrect: boolean attribute set to "true"

This triggers the validation error because "true" is not a valid value for a boolean attribute.

Correct: boolean attribute with no value

Simply include the attribute name without any value assignment.

Also correct: boolean attribute with an empty string

The empty string is a valid value for any boolean attribute.

Also correct: boolean attribute set to its own name

Per the spec, a boolean attribute can be set to a case-insensitive match of its own name.

Recommended: using the modern `allow` attribute

The allow attribute is the preferred approach going forward. It replaces allowfullscreen and can also control other permissions like camera, microphone, and more.

You can combine multiple permissions in a single allow attribute:

Common mistake: trying to disable with "false"

Be aware that the following does not disable fullscreen — the attribute is still present, so fullscreen is still allowed. This would also produce a validation error.

To disable fullscreen, simply omit the attribute entirely:

Why this is a problem

How to fix it

Examples

Incorrect: using Pragma in http-equiv

Incorrect: using Cache-Control in http-equiv

Correct: remove the invalid tag and use server headers

Why this matters

How to fix it

Examples

❌ Bad: using role="presentation" on an <img>

✅ Fixed: decorative image with empty alt (preferred)

✅ Fixed: decorative image with role="none"

✅ Fixed: meaningful image with descriptive alt

❌ Bad: meaningful image incorrectly hidden

Bad Example

Fixed Example — Decorative/Background Video

Fixed Example — Meaningful Video

Examples

❌ Incorrect: using the invalid presentational role

✅ Correct: using presentation

✅ Correct: using none (synonym for presentation)

Other elements where this applies

When to use presentation vs. none

Understanding the Issue

Why This Is Flagged

How to Fix It

Examples

Invalid: Non-standard type value (generated by WP Rocket)

Valid: Standard type attribute

Valid: Omitting the type attribute entirely

Valid: Using a module script

Valid: Using a data block with a proper MIME type

Examples

❌ Incorrect: role="rowgroup" on a <header> element

✅ Fix option 1: Use a <div> instead of <header>

✅ Fix option 2: Use native HTML table elements

Understanding Deprecated Media Types

Why This Is a Problem

How to Fix It

Examples

❌ Incorrect: Using the deprecated projection media type

✅ Correct: Using only the screen media type

✅ Correct: Removing the media attribute entirely

✅ Correct: Combining valid media types

❌ Other deprecated media types to avoid

How to fix it

Examples

❌ Incorrect: role="search" on an <input>

✅ Correct: type="search" on the input, role="search" on the form

✅ Correct: Using the <search> element (modern HTML)

✅ Correct: Standalone search input without a landmark

Examples

Incorrect: using the invalid section role

Correct: remove the role attribute

Correct: use a valid ARIA role if needed

Correct: explicit region role with an accessible name

Examples

Invalid: non-existent ARIA role

Fixed: use role="complementary" on a generic container

Fixed: use <aside> for semantic HTML

Multiple complementary regions with distinct labels

When the content is navigation, not complementary

Valid ARIA landmark roles

Examples

Triggers the validator error

Fixed: use the semantic element (preferred)

Fixed: keep the container, apply a valid role

Full document example with two sidebars (each labeled)

Examples

❌ Invalid: street-address on an <input>

✅ Fix: Use a <textarea> with street-address

✅ Fix: Use line-specific tokens on <input> elements

Summary of allowed pairings

Examples

Incorrect: tabpanel role on an article element

Correct: tabpanel role on a div

Correct: Nesting an article inside the tab panel

Full tab interface example

Examples

Incorrect: using `Pragma` in `http-equiv`

Incorrect: using `Cache-Control` in `http-equiv`

❌ Bad: using `role="presentation"` on an `<img>`

✅ Fixed: decorative image with empty `alt` (preferred)

✅ Fixed: decorative image with `role="none"`

✅ Fixed: meaningful image with descriptive `alt`

❌ Incorrect: using the invalid `presentational` role

✅ Correct: using `presentation`

✅ Correct: using `none` (synonym for `presentation`)

When to use `presentation` vs. `none`

❌ Incorrect: `role="rowgroup"` on a `<header>` element

✅ Fix option 1: Use a `<div>` instead of `<header>`

❌ Incorrect: Using the deprecated `projection` media type

✅ Correct: Using only the `screen` media type

✅ Correct: Removing the `media` attribute entirely

❌ Incorrect: `role="search"` on an `<input>`

✅ Correct: `type="search"` on the input, `role="search"` on the form

✅ Correct: Using the `<search>` element (modern HTML)

Incorrect: using the invalid `section` role

Correct: explicit `region` role with an accessible name

Fixed: use `role="complementary"` on a generic container

Fixed: use `<aside>` for semantic HTML

❌ Invalid: `street-address` on an `<input>`

✅ Fix: Use a `<textarea>` with `street-address`

✅ Fix: Use line-specific tokens on `<input>` elements

Incorrect: `tabpanel` role on an `article` element

Correct: `tabpanel` role on a `div`

Correct: Nesting an `article` inside the tab panel

Incorrect: `tabpanel` role on a `<ul>`

Correct: `tabpanel` role on a container wrapping the `<ul>`

Correct: Using `<section>` as the tab panel

❌ Invalid: `tel-national` on `type="tel"`

✅ Fix option 1: Change input type to `text`

✅ Fix option 2: Change autocomplete to `tel`

Incorrect: space after the colon in a `tel:` link

Incorrect: space after the colon in a `mailto:` link

Correct: `mailto:` with no space

Visual formatting vs. the `href` value

Fixed using the `http-equiv` form

❌ Incorrect: Using `windows-1251` charset

✅ Correct: Using `utf-8` with `http-equiv` syntax

✅ Correct: Using the shorter `<meta charset>` syntax (preferred in HTML5)

Incorrect: Using `windows-1252` charset

Correct: Using the short `charset` declaration (recommended)

Correct: Using the `http-equiv` pragma directive with `utf-8`

❌ Incorrect: `role="textbox"` on an `li` element

✅ Fix: Nest a `div` with `role="textbox"` inside the `li`

Recommended: using the modern `allow` attribute

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Ship accessible websites, faster.