I use the Restart button that is given by a add-on (currently "Restart My Fox") .. but sometimes I am too late and Firefox has hogged up. (I keep a PsKill Firefox button on the taskbar). An auto-restart every hour would be nice, allowing that there has been a one-minute lull, I have not seen a restart tool that works automatically. Doing this by seconds is dumber than Clinton and Trump combined.
Similarly, there are issues with the Session Manager extension, to save the previous work, lately it has been giving blank "New Tabs" too frequently, so I am going back to the TabMixPlus or Firefox session manager method. Afaik, none of these are great, but they do help. I'll try Session Manager again in a month or so, it has been pretty good over time.
My related problem is that Firefox tends to go in "(Not Responding)" mode too easily (the hogging up mentioned above.) No other program does it, and it can happen with only 10 or so tabs open.
Firefox still remains my browser of choice, the multi-row and flexibility of Tab Mix Plus & Lazarus are the two main reasons, plus I use the toolbox bar as a type of pim and handy-dandy place that works well for some stuff.
Lazarus may be on Chrome. Plus, I still like Firefox in general more than any alternative, although Pale Moon and Vivaldi get some use, along with Chrome and others. Chrome is used to create shortcuts pinned to the taskbar (Evernote, Google Docs, Radionony for bluegrass gospel, etc. and those come up in a Chrome box, which is fine. Also it is a bit stronger for Google - Docs, Inbox - types of stuff.
Linkman has a little lull in searching on my moderately fast Dell, due to the 100K+ bookmarks, while it seems to do fine on a stronger Dell. Thus, I plan to test Cacheman, also by Outertech, to see if one OT product helps another. (Already have a license, maybe.) The best solution is probably an SSD.