Version diff preview for new type extension (mimetype)

Hello everyone,
I have just added a new file extension to my Nextcloud. To do this I created config/mimetypealiases.json using this content :

“rpy”: [“text/x-python”]

I then used the commands :
occ maintenance:mimetype:update-js
occ files:scan --all

Almost everything is working fine, I can open the rpy files as python with the file viewer. My issue is that the file versioning comparison can’t show the previous versions. Here is how it looks :

Does anyone know how I can activate the file preview ?
Thank you in advance

Hello @Jinkso ,

welcome to the community of Nextcloud.

You started a topic in support category.
Unfortunately you ignored the template and a lot of information to help you is missing.

Please add all necessary information like Nextcloud version, webserver type and version, os version, related log file content.

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