Gunnar.See Lyx3.ico attached for us windows users
oops, my mail scanner didn't like an .ico file being rec'd so here it is again (he hopes!) with the extension changed to .txt (rename to .ico on receipt).
Image may need some further image tweaking to loose the background on a win box.
Rob S -- R D Saunders Hydraulic Research Group Department of Civil and Environmental Engineering University of Southampton UK