Firefox 44 due later today. Mozilla have a new policy for Firefox add-ons which means they'll have to be 'signed' (approved) by Mozilla to work with Firefox, any unsigned add-ons won't work. Starting with v43 there's an option to run unsigned add-ons but from v46, in about 12 weeks time, the option will be removed and unsigned add-ons won't run. Reason is that, while most people get their FF add-ons from AMO (
Add-ons Mozilla Org), add-ons can also be provided anywhere else on the web and unscrupulous developers are taking advantage of this to provide malicious add-ons (the 'great little freebie' that's actually...). A lot of dissent from techie users but looks like it's going to happen and it'll probably benefit most Firefox users. So, if some of your add-ons stop working, probably it's because the developer hasn't had them signed. Could be because they're potentially 'dangerous' or, more likely, they're old. Could still be safe and very useful but the developer gave up maintaining them years ago. So, could be time to look around for alternative adds-on. Or an alternative browser if it really pisses you off. So far as I know, it won't affect Firefox spin-offs such as Pale Moon, which (
SFAIK) are developed and maintained from an older version of Firefox when previous changes pissed some people off.
