Linux (deb)
apt install ./eleshop-power_….deb pulls Electron deps (libgtk-3-0, libnss3, etc.). Extra steps:

USB serial (P4305 / Techmize CDC): user in dialout, then log out/in
sudo usermod -aG dialout "$USER"
USB TMC (ODP / Siglent USB): user in plugdev (udev rules ship with the .deb)
sudo usermod -aG plugdev "$USER" then unplug/replug the instrument

