Since about a week ago my girlfriend's Firefox 19.0.2 started to crash with low memory message. She's using a laptop with 3 gig of memory and Windows 7 32. Her add-ons are adblock, WeatherBug and some spellcheckers. I reinstalled her browser and also installed Memory Fox plugin. It didn't help. Crashes occur once in one or two days after several hours of browsing. I asked her to save the "about:memory" page when the low memory message appears. These are the first lines: 1,347.68 MB (100.0%) -- explicit ├──1,007.93 MB (74.79%) -- images │ ├──1,007.71 MB (74.77%) -- content │ │ ├──1,007.65 MB (74.77%) -- used │ │ │ ├────601.40 MB (44.62%) ── raw │ │ │ ├────361.11 MB (26.79%) ── uncompressed-nonheap │ │ │ └─────45.14 MB (03.35%) ── uncompressed-heap │ │ └──────0.06 MB (00.00%) ++ unused │ └──────0.22 MB (00.02%) ++ chrome She also sent me the page just after she started Firefox (with her pinned tabs) and there are no such memory figures. Unfortunately I can't be more specific. She can't say if she changed something recently and she's also unable to cause it to happen when I am there.