Hi! I have a solution to your problem. I usually have 50-70 tabs open & even if I rarely have to stop firefox in task manager, I NEVER lose my tabs!! Normally, when I am done & close firefox, I watch task manager, & it make take even a few minutes for it to close - best to allow it to do this before powering down! I then run ccleaner, tho be careful with options & things u delete - for firefox, I ONLY delete
Internet cache, Cookies (except those in ccleaner exclusion list!!), Download history. I also compact database.
1st of all make sure u are using a version of firefox (I use 13.0.1)
that has in firefox options, General tab, "Don't load tabs until selected" - ck that off!! This is HUGE!! Imagine trying to open 86 tabs at once lol.
Also, make SURE in options, General tab, make sure when firefox starts, you have picked "show my windows and tabs from last time" is set.
I use these add ons:
this is my final list after MUCH experimentation- i doubt i will change it anytime soon"
adblock plus, bookmark current tab set (set to AUTO!! bookmark ALL!! tabs upon closing - just in
case), deduplicate-tabs, flashblock, load tabs progressively(set to 1 at a time),
paste email(original), unload tab (load selected tab/immediately/dim unloaded tabs), visited, &
tab utilities(i put tabs on LEFT column & stack related ones to save tons of space - i do NOT put
them on top/multirow - slows things down)
i hit ctrl - left slash to hide & unhide the tabs when nec
TO STACK RELATED TABS, SELECT MUTIPLE ONES, RIGHT CLICK & PICK STACK!!!
The keys to never losing tabs is the bookmark current tab set & load tabs progressively(set to 1 at a time) - if u ever lose your tabs, just go to most recent tab bookmarks, open them all & load tabs progressively will INSURE all tabs will be loaded, one at a time & unload tab will unload & dim them & keep them available for opening later on!!
You can tweak the options of above to your taste.
Tab utulities has the wonderful option of setting ctl-tab to switch between the 2 most recently accessed tabs!!
I NEVER use app tabs - no need - they can cause trouble.
Also, no need for Tab Groups Manager addon - it is ok but slows down firefox too much.
Tab utilites stacking ability is even better than the above Manager's tab grouping.
I only had to open all tabs from a the latest bookmark once in maybe a month. Most times, if I have to stop firefox in task manager, the tabs reappear when I restart.