TL;DR
The game forces us to use a mouse shortcut for removing filter on the quickbar and inventories.This is a problem when playing on a laptop without mouse and there is no apparent reason to force that.
What ?
As a person playing a lot of factorio when traveling for work, I can't use my mouse.The new quickbar uses links, so the filter removing button is now a core action in the game.
When I tried to remap this action the game told me I had to use a mouse related shortcut.
Why is that ? Why can't I use a keyboard key ?