Many add-ons have somewhat spookiy authorisation requirements, such as “access all of your activity”. In many cases this is justified by it’s function, and of course there isn’t any problem with it as long as we’re sure all this data stays on your computer and isn’t shared with any remote server. How are we sure of that tho? Is there an easy way to check for each add-on ?
It just isn’t easy. You can read permissions and try to read the source, but it requires some expertise.
For smaller extensions, you can start by looking at the
manifest.jsonas this file is the entry point. You can see which part of the code needs access to 'everything' and go from there.https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json
For example, with Instance Assistant for Lemmy, you need to give access to all sites because it needs to run on any Lemmy site and that's not something you can hardcode in.