Ok, so are you saying you are an IE6 user? ;)
And performance is 20x worse only if you can't really code in JS - good idiomatic JS is usually much faster. If you don't believe me, just see how JS compares to C in the Great Language Shootout - in one case the benchmark program is even faster than C and median from all teste is JS only 4x slower than C.
and Java programs crash too if the programmer fucks up.
Oh, yeah. The last time I saw Java application crash was Eclipse on Linux a week ago. It crashed in native code - the culprit was broken GTK, which is heavily used by SWT. Besides that, I've seen lots of complex Java applications misbehaving in one or another way, but they never crashed leaving me without my data.
Just install a global catch-all exception handler and it just can't crash due to a bug in the application. And probably all GUI frameworks already contain a global catch-all handler. So the only bad thing that can happen is that the application does not do what you asked it for - you get a stacktrace instead and you can continue using the application (e.g. saving the file). But it won't crash. Even if it is out of memory, it will be sluggish, but still won't crash. It might crash only if your CPU/memory/OS/JVM is broken or you do something very nasty in native code through JNI (but then you just asked for it).