[twinsen] [2.0.12] Flat Character GUI cannot be closed by pressing hotkey again

[vadcx]

Default keybindings are:
Open Character Logistics: F1
Open Character info: F2
Open Character crafting: F3

Expected:

Pressing the same button again to close the menu if it's already open (otherwise switch to the respective menu first).

Actual:

Settings -> Interface -> Flat Character GUI = ON

1. Press either hotkey once to open menu
2. Press the same hotkey again, menu remains open (expected to close like ESC or double "E")

Settings -> Interface -> Flat Character GUI = OFF
1. Double F1: opens and closes, good
2. Double F2: only opens but doesn't close, bad
3. Double F3: opens and closes, good

Edit: the second part has Flat GUI set to OFF