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HTML Guide

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Saw “<!--” within a comment. Probable cause: Nested comment (not allowed).

Nested comments are not allowed in HTML. When you place an opening comment tag <!-- within an existing comment, it causes a parsing error.

To fix this issue, you should avoid nesting comments. If you need to include multiple comments in your HTML code, you can separate them or consider alternative ways to convey the information without nested comments.

Here’s an example of a nested comments, which is not allowed in HTML:

<!-- This is a valid comment -->
<!-- This <!-- is not allowed --> nested comment -->

To fix the nested comment issue, you can rewrite the comments like this:

<!-- This is a valid comment -->
<!-- Avoid nesting comments and provide comments separately -->
<!-- Another comment here --> 

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