said by mouse:
I am still a bit baffled and unsure how to evaluate that threat.
Well as already noted an extension is just another part of the browser so it can access data.
That said many popular extensions, for FF anyway, are open-source so the chance of them being malicious is reduced (although not eliminated).
I guess it comes down to trust. I haven't heard of any major extension being malicious but you might not find out until its too late.
Reminds me of Sieur Clubin in Victor Hugo's Toilers of the Sea
. He was considered extremely honest and trustworthy until the day he disappeared with all the loot.--
Don't feed trolls--it only makes them grow!