NetBird sends its tray icon as a pixmap, so an icon theme can't replace it. patch.py rewrites the 48x48 PNGs embedded in netbird-ui in place: the glyph is scaled to 80% to get Breeze's padding and the white variants take the panel text color (#dedede). A pacman hook re-patches the binary after every netbird-ui upgrade, and restore.sh puts the original back.