Well, I suspect people care when the program hangs and they lose their work from the past 2 hours. So maybe make auto-save the third feature

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Sigil
used to be rock-solid, which was a major bonus, but I've experienced a number of crashes in 0.3.4 (which I suspect are related to Qt behaving badly, but I'll probably need to run it in the debugger to see what's happening, since they're quite random), and while 0.4.0RC1 has some nice features it's just too unstable to use.