I-Firefox Isithangami Sokwesekwa

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.

Thank you for your assistance in advance. Since I updated my browser, I've encountered some issues when trying to maximize the virtual screen in my tv. I use a Mac and connect the screen to a web TV to watch YouTube in my big tv. However, when I click to maximize the window, the connection becomes unstable, and the virtual screen disappears every time I click the YouTube icon to do this. This problem never occurred before. I would appreciate your help in resolving this issue. Please let me know if you require any additional information from me.

Most of the time I cannot print my emails because an "add blocker" is installed. So now, I no longer use Firefox, since when I use Microsoft, I have no such problem.

Unable to run firefox. I get the error message. (see attached screenshot) After terminating firefox processes, I attempted to create a new profile. and see an error message. (see attached screenshot)