Nextcloud: Stored XSS on Share-popup of a directory's Gallery-view

Hi,
Nice with the program launch! Congrats!

I noticed that there was a Share-icon when toggling to the Gallery-view of a directory under “Nextcloud Files”:
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If your directory has a malicious name such as a HTML-payload: <img src>, this HTML will run when clicking on the Share-icon:
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I see that you have a proper CSP in place, but remember that Internet Explorer is not there yet:
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Also, since any user could create files, a user could potentially execute this for an admin (if that admin is not using a CSP-supported browser that is).

Let me know if you need more information.

Regards,
Frans