Regarding the not verified message:

In the future, Firefox will refuse to run unsigned extensions. However, the first step being taken in Firefox 40 is to warn you that you have some so you can check for updates and/or inform the publisher about this impending problem. Active publishers are likely to take care of this in time. That is, they need to do is submit their add-ons to Mozilla for review and signing some time before Firefox 41 is released.

But inactive publishers of legacy extensions probably will not take action to keep old extensions working. If those extensions have open source licenses, someone else could take them over. Are there particular extensions you're worried about losing?

Missing buttons or lack of function:

Firefox 40 marks the end of a transition for how add-ons interact with the user interface, and the old "widgets" module has been removed. I have seen reports of this affecting 1Password version 3 (company recommend switching to version 4) and Skype Click to Call (not sure what Microsoft intends to do). Other extensions might also be affected. Which ones are you noticing have problems?

By the way, the Skype Click to Call extension can be hacked to work in Firefox 40 (this hack restores the function of spotting numbers, but leaves off the toolbar button): https://support.mozilla.org/questions/1077493#answer-767133

kimzkyle said

Extensions show browsing protection not verified. If I wanted these extensions gone I would have deleted/disabled them myself. How do I get them back? Do I need to reset Firefox to older version?

Password Box, F-Secure Browsing Protection, F-Secure search, Ebates Cash Back & Skype Click To Call are the extensions that are showing "not verified".

Okay, "not verified" is just informational for now. Those publishers hopefully will issue updates in the next several weeks.

Which ones are actually broken? Other than Skype Click to Call, which I already know is broken.

Password Box.

kimzkyle said

Password Box.

Yes, I see, that one installs, but no toolbar button appears, and probably other aspects do not work, either.

This problem was known during testing for the past several months, but apparently Intel/McAfee didn't prioritize an update for Firefox 40. Could you submit a support request to them?

Unlike Skype, I'm not willing to hack a password-related add-on.

If your online life cannot proceed without PasswordBox, you might need to return to Firefox 39.0.3, bearing in mind the security issues. This article has more information: Install an older version of Firefox.

Thanks for your help. I sent a support request to Password Box. Intel is working on it. In the meantime, they suggested using Chrome or IE (barf) until they apply fix for Firefox 40. So, I will probably be using Chrome until the issue is resolved. Thanks again for the help.