Suggest using a different browser? Possibly use Google Chrome and Firefox, google chrome for whatever you may be doing, and keep Firefox open with the Login tab. Sometimes when I use Google Chrome I noticed it logs me out a lot more then Firefox does.
So basically, whenever I'm on FH, I have both Firefox and Google Chrome open. Firefox with the Login Tab that we have to keep open, and Google Chrome with whatever I may be doing, including switching through tabs a lot etc.
Lemme know how this works out? I hope this made sense. ^