Every Firefox session, I use plenty of tabs, stacked atop each other in a vertical bar along the left side of the screen, using an extension named "Tree Style Tab" and it… (tuilleadh eolais)
Every Firefox session, I use plenty of tabs, stacked atop each other in a vertical bar along the left side of the screen, using an extension named "Tree Style Tab" and its affiliated extension, "Open Link in New Tab" These never caused a problem for me during the first two years of use, but in the last three years or so, Firefox began to eat huge chunks of my memory.
Since I use Tree Style Tab routinely to keep perhaps 30 or so tabs open as I do research, my first thought was something had changed with one or both of the two extensions, and they had developed a problem with using memory efficiently. To test my hypothesis, I simply disabled both by starting Firefox in SafeMode.
Of course, that also disabled every other extension and plug-in, as well, but proved that my problem does not come from any extension or plug-in. Because while in SafeMode, Firefox continued to eat memory at a phenomenal rate until operations became extremely slow and the system finally froze in-place. That is, I began with some 3.1 Gb of physical memory (my 32-bit XP Pro SP3 system retains 1Gb from a total of 4GB), but soon found Firefox was using a whopping 1.7 Gb for only 20 tabs which should have taken no more than perhaps 300Mb, at most.
Yes, I have varied the mix of tabs, so if there were any memory-intensive connection / website, that connection would have stood out plainly. But the same effect is observed no matter how the tab connections are varied.
All my plug-ins and extensions are up-to-date, and Firefox is at version 38. All caches have been cleared.