As the comment says: prevent clang(_complete) from crashing my editor
_NET_CURRENT_DESKTOP is a root window property, want _NET_WM_DESKTOP instead
Remove superfluous non-const methods
Don't take alpha from window pixmap into account (it's only 24bit anyway)
Immediately update at least once after mapping the thumbnails
Immediately fetch the window pixmap anew when {un,}mapping
Create a replacement pixmap when window pixmap is not available
Make x_client an observable
Replace configure notify handling and repeated window pixmap loading by observable calls