[iamnotacrook]

I think you need to make it clear to your colleagues that you need to strongly reconsider any possibly that you EOL browser a before browser b supports plugins (specifically ublock origin and noscript) as a lot of your core users will simply not use a browser without them. They're not a "nice to have" - they're what they need to even consider using the browser. Otherwise they might as well be using chrome, or one of any number of other browsers.