TinyMCE in classic editor does not support modern video formats

[blackstar1991]

WP does not support webp, avi formats for the classic editor. Can someone help and make them uwaliable like in Block Templates ?

[nabilaminhridoy]

Hi there 👋

I’ve tested this issue on the latest WordPress 6.8.3 with the Classic Editor plugin (v1.6.3) and can confirm that the problem still exists.

When trying to insert .webp or .avi files via the “Add Media” modal in TinyMCE, the files are not recognized or previewed correctly.
Meanwhile, the Block Editor supports .webp uploads and displays them as expected.

This seems to be related to the allowed MIME types or TinyMCE’s media plugin configuration in the Classic Editor integration.

Steps to reproduce:

1. Activate the Classic Editor plugin.
2. Go to “Posts → Add New”.
3. Click “Add Media” and try uploading a .webp or .avi file.
4. The file is rejected or not displayed in the editor.

Expected:
The Classic Editor should handle .webp and modern video formats similar to the Block Editor.

If needed, I can help test or submit a patch for this.

@nabilaminhridoy