Button for "select/deselect" all cards in hand

Module Design
1

Is it possible, add a button (similar the flip/unflip button) to the players hand window,
which allows to select/deselect all cards?

2

Thus spake Bayernkini:

Is it possible, add a button (similar the flip/unflip button) to the
players hand window,
which allows to select/deselect all cards?

So far as I know, there’s no way to interact with what’s selected from
traits. It’s something I intend to remedy for VASSAL 4.

–
J.