Critical CSS/Rendering issue across multiple platforms (Moodle, Lumi, Logiquizz)

Hello everyone,

I am reporting a significant rendering issue that has recently appeared across various H5P environments (Moodle via mod_hvp, Lumi, and Logiquizz). It seems like a core CSS or library corruption issue rather than a specific content type bug.

The Problem: H5P activities that were previously working fine are now appearing with "broken" layouts.

  • CSS Failure: In Drag and Drop activities, the drop zones and styling around elements have disappeared, though the content itself is technically "there."

  • Total Disappearance: In some cases, like Multiple Choice Questions (MCQ), the activity becomes completely invisible or fails to render any interactive elements upon visualization.

  • Cross-Platform: The issue is not limited to our Moodle integration; it is also reproducible on desktop tools like Lumi and Logiquizz using the same files.

Steps to Reproduce:

  1. Download an official H5P example (e.g., from the Drag and Drop page on H5P.org).

  2. Upload/Open it in a local environment (Moodle mod_hvp or Lumi).

  3. The styling is stripped, and the activity is often unusable. Note: The activities still appear correctly on H5P.org itself, but the exported files seem to trigger this issue elsewhere.

Context & Observations:

  • We initially suspected a local update error, but since it affects standalone apps like Lumi/Logiquizz simultaneously, we suspect a corrupted dependency or a version conflict in a shared library (possibly a recent update to a common core library used by these tools).

  • Even files that worked perfectly in December are now showing these symptoms.

Has anyone else noticed a sudden breakdown in CSS rendering recently? Could a recent update to a base library (like h5p-php-library or similar) be causing this incompatibility?

Thank you for your help!

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