In the never-ending quest for browser security, Firefox has started implementing safeguards to only allow signed extensions. I found this out after upgrading to Firefox 41 as my installed version of “Deque FireEyes” stopped working. Thankfully, there is a workaround in Firefox 41, but it goes away in Firefox 42.
- Firefox 40: warning only!
- Firefox 41: workaround, via:
xpinstall.signatures.required = false
- Firefox 42: BLOCKED! unless signed