User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:43.0) Gecko/20100101 Firefox/43.0 Build ID: 20151216175450 Steps to reproduce: I just leave PC to 15-20 min. or less-more. Actual results: And browser doesn't ready to immediately work, kind of freezes. That slowdowns and freezes also seen on usual working. As a rule I'd kill the browser process and start by new. Expected results: PC's/OSs setup is 64-bit Windows 10, v10.0.10586.17 (Win10 TH2) (but that's not the case!; for example, Vuze & foobar2000 much better working under the same conditions, others applications), RAM - single channeled 4 GB (always free memory amount - >400 MB), CPU is QuadCore Intel Core 2 Quad Q8200, 2333 MHz (7 x 333). And this is just only with few open tabs, 1-2-4! I think, Firefox devs can do some beatiful workarounds for solving a raised issue, so, firefoxies with PCs specs like mine will browse, work, firefox without this difficulty, and others users even a fortiori!
Do you still see this problem when using a current version?
User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:51.0) Gecko/20100101 Firefox/51.0 Firefox: 51.0.1, Build ID: 20170125094131 I haven't managed to reproduce this issue on latest Firefox (51.0.1) and latest Nightly (54.a01) build. I will mark this as Resolved - Incomplete due to the lack of response from the reporter. If anyone can still reproduce it on latest versions, feel free to reopen the issue and provide more information.