I’ve installed the package cachyos/inputplumber-bin
sudo pacman -S cachyos/inputplumber-bin
sudo systemctl enable inputplumber
mouse is back in desktop mode and have access to menu button yeay
work great with
EDIT:
last inputplumber update broke the steam mode menu (again)
main menu button and right menu are not working.
mouse emulation ok in desktop mode
all buttons are ok in the test tool
suspend button not working