from a Gramps bug report with a proposed PR to resolve it: `The PR is not “allowing pip to modify a flatpak” — it is installing addon dependencies to user data, which is standard practice and explicitly permitted by Flathub.` In this app, add-ons (in this case these are app specific add-ons, not the Flathub use of the term add-on) can be installed with an add-on manager in the app’s toolbar. If an add-on dependency is missing, the add-on manager is supposed to pull in the extra dependencies ...