Disclaimer: I don't know if this has any meaningful security effects. Read the replies below to check what people are saying/recommending before doing this if you're unsure. I haven't personally had any issues [that I know of] since doing this last year.
You might have noticed that when you browse Mozilla sites (e.g. the Firefox add-ons site) your installed add-ons don't seem to work. This is annoying as hell, especially if you have accessibility needs that are met by an add-on. But there's a way to prevent this from happening:
- Type
about:config into your browser address bar (might have to accept a warning message if it's your first time)
- In the search bar of the about:config page, type/paste
privacy.resistFingerprinting.block_mozAddonManager and set it to True
- Type/paste
extensions.webextensions.restrictedDomains into the search bar this time, and edit the entry to remove any websites on which you would like to have your add-ons work (I just removed 'em all)
You dont need the second one, which does something entirely different
And yes, of course it has security impacts. It allows addons to tamper with the installation of addons, a typical privilege escalation that allows them to install whatever they want