UV - Request to multi-viewport selection by shortcut key with mouse click for viewport sync

We can select the Viewport which we want to sync by using “Viewport sync on/off” button.

But customer dislike to use it because it is too small for their operation.

So they are using keyboard shortcut, it was assigned "Viewport Sync On/Off”.

But they also claimed that it is troublesome.

Customer request enabling the multi-selection of the viewports by shortcut key + mouse clicking.

They insisted other vender viewer has such function.