Warn user before reload when in exam mode

[simonbohnen]

Is your feature request related to a problem?

When in exam mode, there is no warning before a reload of the page. All unsaved changes are lost.

Describe the solution you'd like

It would be nice to have an alert before a reload.

Describe alternatives you've considered

No response

Additional context

Discovered together with @coolchock.

[krusche]

We used to have this feature. I'm wondering what happened to it?

[badkeyy]

For me this still works (See Screenshot). In which browser did you test this?

[simonbohnen]

I tested it just now in a test exam in both Chrome and Arc, and when I press Cmd+R it doesn't show a warning.
Last time I tested it in a "real" exam, also both in Chrome and Arc I thing.

[badkeyy]

Ah yes you are right I confused myself by already testing my fix - sorry (I was confused because it did not show my custom message in the popup and therefore I thought this is already implemented). I will open up a PR.