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This also changes the panning behavior in the easel. Space bar is no longer used, because it was sometimes interfering with content shortcuts.
>
> This is fixing a bug in Zombotron. I'll try to come up with a test case
> for it.
>
Note that I'm not saying that absolutely every change has to have 100% test
coverage. We have to make tradeoffs between required effort and return
value for that effort, obviously.

Comments, OTOH, should go in with such a change.