Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
HTML issues tagged as tt.
<tt> tag, used in HTML4 to apply a monospaced (fixed width) font to the text, was deprecated in HTML5. Instead, you should use CSS to apply the desired font.
Example, instead of this deprecated code:
<tt>This is deprecated</tt>
You can define a monospaced text using
<span style="font-family: monospace;">This is monospaced text</span>
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