Handle reloading

[mlhetland]

It seems that reloading the contents of the window (cmd-R on macOS, for example) causes trouble. I, at least, consistently just get a plain-text Not found.

Not that one necessarily would need to reload – I just instinctively did it to get rid of a button focus while prototyping – but the fact that there's an easily available command that instantly breaks any app seems brittle :-)