When uploading QTI 2.1 packages that include videos with WebVTT caption files in Canvas LMS, we encounter an issue where the WebVTT files fail to load, resulting in an "Unsafe attempt to load URL" error. Additionally, it appears that the crossorigin="anonymous" parameter within the <video> element is being filtered out during the import process. 

I tried multiple ways to load video and VTT files, both bundled with the QTI package, both coming from different CDN links and the last one with VTT bundled in the package and the video coming from a CDN link. None of the combinations worked for me.

Please provide any insights, workarounds, or solutions that could help address this challenge. I am open to suggestions, experiences, and best practices from those who may have encountered and overcome similar issues.