Does the pen in Excalidraw have a rubber function?

What I’m trying to do

I’m trying to use my pen (HP active pen G3, registers as Wacom HID 486E Pen) to draw in Excalidraw under Linux (Zorin OS). This works nicely and I can use the upper side-button to move the canvas. The lower side-button and the top button has no effect unfortunately.

Ideally I’d like to have the lower side-button to activate the rubber function.

Things I have tried

I tried debugging the pen with xev and finally found that with the input-remapper-gtk the side buttons show up as “Button TOOL RUBBER” (lower side button) and “Button STYLUS” (upper side button). So it seems the pen works and the assigned functions from the Wacom driver as well. So maybe it is only a question of if and how the Excalidraw plugin supports this action to use the lower side button as a modifier for activation the rubber?
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