Display panels

[felixfung]

Identify panels by _NET_WM_WINDOW_TYPE_DOCK? Then create ClientWins and put them in their own dlist in MainWin. Do not feed them into clientwin_move(), clientwin_map(), rather write a new function panelwin_map() that creates cw->destination, call clientwin_render(), XMapWindow().

Whether user input should be allowed into panels... I don't know. If needed, the list of ClientWins should be parsed here:

skippy-xd/src/skippy.c

Line 921 in b0fa809

else if (mw && wid) {

Another config option would be whether the usual expose windows should overlap with the panels.