Fired up Firefox this morning and discovered that all my add-ons were disabled. Turns out there is an issue with expired certificates. I have switched to Opera until there is a fix for Firefox.
I'm still using 56.0 and it hit me yesterday out of the blue. Just restarted it now and still have ads!! :( I was getting ready to update to the latest version, so maybe this is the time to do it. :)
This is interesting. I also am using 66.0.3 and about a minute after starting, my add-ons appeared. It definitely was an issue and apparently Firefox fixed it quickly.
I have version 66.0.3 also, but like Tom, none of my Add On are working this morning. Firefox has been acting up the last week or so, guess I'll have to go back to Microsoft Edge. I've read in forums that Firefox seems to work ok for months then just goes wacko.