Show text cursor when moving cursor over panel/note label

[aljelly]

I think it would make it a lot more obvious that you can double click to rename a panel if the text cursor is shown when moving the mouse over it.

But only do this when hovering over the label on the header bar, don't show the text cursor for other parts of the header bar.

By text cursor I mean this:

[spheras]

mm I agree that cursor would help to know you can edit the label... but maybe the user expects to do it with a single click... You know, the problem I see is with that cursor you don't expect to move the window through the header... you expect to rename it if you click. Now the label is at 100%, first we should reduce to only the text printed. We could try and see the result.