HTML API: Reconsume script data terminating less-than tokens

[sirreal]

Summary

• Reconsume a non-matching byte after < while scanning script data.
• Prevent less-than sequences before the real </script> closer from making normalization drop the script element.
• Add coverage for script less-than parsing and normalization cases.

Inputs like <script><</script> or <script>whatever… <</script> would fail to parse at an incomplete token.

Trac ticket: https://core.trac.wordpress.org/ticket/65372

Testing

• Focused script parsing and normalization PHPUnit coverage passes.
• See HTML API debugger text example for this PR.

Use of AI Tools

AI assistance: Yes
Tool(s): Codex
Model(s): GPT-5.5
Used for: PR description cleanup and code review.

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[sirreal]

It's already advanced past the <, so this ++$at; causes the < to miss the start of the closing </script> when it's the last byte inside the tags.

wordpress-develop/src/wp-includes/html-api/class-wp-html-tag-processor.php

Lines 1564 to 1570 in 0a9838d

	/*
	* Everything of interest past here starts with "<".
	* Check this character and advance position regardless.
	*/
	if ( '<' !== $html[ $at++ ] ) {
	continue;
	}

[github-actions]

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