[mikepurvis]

I think I must be hitting something like this too— Mid 2014 MBP running 10.11.6. I tried Quantum when it came out and used it exclusively for about a week, but there were just a myriad of small problems around performance. It would eat CPU and RAM, input would lag especially text entry, Hangouts didn't work, etc. And then on top of that a bunch of annoying interop issues like problems with the 1password extension ("the add-on could not be downloaded because of a connection failure"), not being able to right-click selected text and access the Services menu.

I really want to love Firefox, and I'm giving it another try with 59, but at the end of the day I need my computer to work for me. :(