Modifying confinement impossible

On a default install of Ubuntu 22.04, the HTML help documentation for LibreOffice is installed in /usr/share, which is absolutely the correct place to put it. However, this makes it unavailable from Firefox snap, and I have no option to change this.

As far as I can tell, not letting the user change confinement is a philosophical decision meant to enforce the file system hierarchy. And this seems to work fine most of the time, except when it sometimes breaks things completely with no possibility of fixing them. /usr/share is definitely the correct place to install the LibreOffice help apt package (and not in some specific user's home folder), so it should be possible to set the confinement of Firefox to access /usr/share as read-only.

The decision to hard code /home and not let the user configure anything about the confinement of an app from the snap store (not even switching an app from strict confinement to classic) baffles me, because it seems obvious that a user would only go looking for the setting to modify confinement for a specific app to fix something that's expected but broken. Also considering access to /home kind of negates any sort of confinement because it enables access to scripts that will be executed at the next login.

Please don't close this issue report without suggesting any sort of alternative for this specific issue/this type of issue other than what I suggest: Letting the user make changes in an emergency/breakage.