Just checking back in.
Since the memory issues here:
http://forums.mozillazine.org/viewtopic ... &t=3038045
and here:
forums.mozillazine.org/viewtopic.php?f=23&t=3038136
I'm now running:
Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:59.0) Gecko/20100101 Firefox/59.0 ID:20180215111455
and it seems to be using less than half of the memory it was before. I ended up NOT having to change from 64 bit to 32 bit, at least not for now.
I did lose a bunch of tabs, so I'm not sure if or how much that might be related.
I think I am going to hold on on trying the version 60 for now, as well.