[gpm]

That's a really old version of firefox, probably an API has changed with my workaround.

I know of an API change that means the official hotfix won't work (whether you install it my bootleg way or the official studies way).

My recommendation is to upgrade your firefox version.

[Alphos2000]

The reason I don't want to upgrade is because I don't want to lose all my legacy addons, a lot of them dissapeared and there are no alternatives. I can't understand how Mozilla can break my browser remotely and force me tu upgrade to a more restricted browser...

[gpm]

Mozilla didn't really "break your browser remotely", it's more like there was a time bomb included that just went off.

If you try hard enough you can probably fix your browser, unpack the .xpi (it's just a zip), look at the source in experiments/skeleton, and try to figure out how to run something similar in the browser console.

But I really can't recommend doing this, I appreciate it's painful, but what you're running right now is massively insecure, there are published exploits. You're just asking for viruses by interacting with the internet using something that old.

[NopesNopesNopes]

Install WaterFox, same old FF56 but the legacy addons are still working.