Kntnt Fix Colon in Fragments of Relative URLs

This is a must-use plugin for site administrators and developers who publish content containing relative links with fragment identifiers. It addresses a specific technical issue where colons within URL fragments (like #fn:1) are incorrectly stripped by the platform's content sanitization, causing footnote links and other anchored references to fail.

• Automatic Fragment Correction: The plugin processes post content before it is saved, scanning for id, name, and href attributes. It replaces any colon within a fragment of a relative URL with a dash, ensuring the link remains functional.
• Targeted Operation: It only modifies relative URLs and protocol-relative URLs, leaving absolute links (those starting with http:// or https://) completely untouched to avoid unintended side effects.
• Compatibility Focus: It is designed specifically to resolve conflicts with HTML generated by Markdown Extra and other parsers that use colons in footnote anchors, making published technical and academic content more reliable.
• Low-Impact Integration: As a must-use plugin, it loads automatically with the platform core. The code executes during the content saving process, requiring no configuration or ongoing management after installation.
• Pre-Sanitization Processing: The replacement occurs before the platform's KSES HTML filtering system runs, ensuring the corrected URLs are the ones validated and stored in the database.