Describe the new feature

It would be very useful, to have opportunity to execute external command with right click on selected cells. It would suffice to have one defined somewhere in Preferences for example. The point is to give freedom to process perfectly browsable data to the user.

From this point view in version 3.11.0 there is a problem which did not occurred in the older 3.8.99
one cannot unselect one cell from selected rectangle of cells , the selected rectangle is not the same any more and the one cell to be excluded is asking to be edited (on views as well).

Anyway, even though it would be of great help to have it

Kind Regards
Thomas

Additional info

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