Click on the top node of your rig, then hit that tool, and it selects all controllers (or whatever) that have keyframes on them- below this top node.
If nothing is selected. It will select all the objects with keyframes.
>> So it's a quick "select all" if you don't have a body picker and that way it let's you move all the keyframes in your scene.
Thank you Jean-Denis Haas for the script idea.
Donate if you find it useful.
Cheers,
Truong
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