I see here that this may be resolved now (last post in thread) https://github.com/BrowserWorks/Waterfox/issues/3628
BTW, I just saw that Waterfox doesn't run on Win 8.1 anymore, I wonder why, because Firefox still works just fine. Although I've just read that Firefox will stop updating itself in March 2025.
waterfox is no longer based on esr, more the current stable - which is not able to run win7/8. the authors have seen that esr will be a dead end and lacks of features which are vital for current browsing. esr has several issues since month which wont ever resolved. in plain: its outdated, the stable build moved on, and porting back code is not possible.
You are affected if you are using a version of Firefox earlier than 128 (or ESR versions earlier than ESR 115.13 for long-term support users). This is due to the root security certificate expiring on 14Mar2025. To avoid problems, update to a newer version of Firefox before then. (You should probably bite the bullet and update to at least Windows 10, 8.1 is ~12 years old & rather long in the tooth.)
the new certificate started in april'24, with firefox 115.13 esr and with 128 esr, and its forks. thats why older extensions (5 years or more) were resigned. older versions are not able to use extension with the new certificate when their current cert run out in march'25
That's the thing, you can't update Chromium and Firefox based browsers on Win 8.1 anymore, I think it's a shame. They are basically forcing you to buy a new machine with Win 11. Thanks for the info. I also noticed that Firefox has a weird bug on Win 8.1, the graphics on websites (like Yahoo Finance) get morphed, you don't see this with Vivaldi. Firefox truly is crap.
firefox 115 esr has unresolved issues for win7/8, never will be. the authors of waterfox know that and switched this early.