For people regularly doing resizing it would really help to have accelerators for the Width, Height, Size and Mode, presumably W H S and M, and the modes could have accelerators 1-5 (or some other sensible choice), which on choosing would select the entry of that position and focus on the following dimension box.
Choosing M would focus on and also pop open the Mode. I think it could also pop up an unobtrusive tooltip about using direct accelerators for its values, here suggested as 1-5.
For what to do if W H or S are chosen and the mode is not appropriate so the box isn't present there are several courses - 1. ignore it, 2. change the mode to whatever was last used that was appropriate, 3. change the mode to a fixed thing and pop it open the person can then adjust or tab onto the dimension value. I think anyone using it regularly would pick up on the direct accelerators.
I don't think the other boxes need accelerators as much as those ones.
Resize / Accelerator Keys
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