Firefox Support Forum

I am a Salesforce (improveit! 360) user, exclusively browsing with Firefox for over 12 years without any problems. The most recent Firefox update 125.0.2 (64-bit) has caused an issue with my staff calendar. I have reached out to improveit! 360 they are a force.com developer and they will not help, said the error is caused by Firefox interpreting the code. I have figured out a work around to get the calendar to load correctly for a short term solution. Below is a screenshot of the error, any help would be greatly appreciated.

I have language set to English (GB) but am being constantly annoyed with words like "colour" being underlined as badly spelt. Why aren't you using an English (GB) dictionary?

Whenever I have Firefox open on Windows 11, my windows key doesn't work. I can assure that its Firefox because whenever I close it, the windows key starts working again. This is really annoying because I normally use the keyboard and having to move my mouse to the bottom just to open the menu gets annoying quick.