
The head developer has plans of reinstating the Firefox compatibility layer in the upcoming update to resolve this, however in the mean time for those that need a fix now follow these instructions

*In the url bar, enter "about:config" without quotes. From there search for "general.useragent.compatMode.firefox". Locate where the value is set to false, and simply just double click on it to change it to "true". Also if websites still give you false warnings to update your browser, you may also override site specific User Agent settings to identify itself as a later build of Firefox. To do so, again open about:config and this time create a new string. It should look something like this:
general.useragent.override.domainname.com
Now as a value enter in the User Agent of a newer build of Firefox, for example: Mozilla/5.0 (Windows NT 6.0; rv:31.0) Gecko/20100101 Firefox/31.0
That should resolve the issue of website compatibility issues in the mean time. However note this will NOT resolve issues with incompatible or broken extensions. Efforts are being made to create static releases of troublesome addons, but so far there are very few available, hence why I don't like to rely on too many addons. Learned my lesson with that using Firefox over the years with it's unneeded and unnecessary updates always popping up, only developers where very eager to provide fixes since such vast majority used Firefox..... With such little userbase compared to larger browsers, getting the attention from these authors is far harder to accomplish.
Hope this comes to use for those facing issues, fight for your browser choice freedom!
