In older versions, dragging a branch tag in the Commits window would pop up a dialog letting you choose between actions such as "Set <branchname> to <targetSHA>", "Cherry-pick", and the like. Now, there's a new, simpler popup menu with the choices, and it's easier to use.
In my experience I always use dragging to move the tag to the target commit; I've also noticed that this is the top choice in the menu. However, the menu is placed so this top choice isn't yet selected; you have to move the mouse after you drop to choose the item and before you click to choose it.
It would be great if the menu popped up right under the mouse, so that a second click would immediately move the tag. Yes, that may be hazardous in that unaware users might accidentally make the default choice, but they could always drag the tag back.
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