Fix move selected to top

[m-kuhn]

Fix #28914

@troopa81 this is a partial revert of #8725 .
According to the description of #8725 this was not part of the fix, but I'm not entirely sure. Do you remember why you changed these lines?

[nyalldawson]

Could you add a test for this? This feature breaks all the time...

[troopa81]

@m-kuhn I don't remember exactly why I did this, it was not indeed the main part of the fix. I think it was to avoid calling sort when it doesn't need to (but I understand it needs to for some reason).

[stale]

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