Pixel width of empty space between tiled windows. Negative values cause overlap.
Set this to the opposite of border_width to collapse the border between tiles.
Disable by setting to 0.
+.It Ic urgent_collapse
+Enables hiding of placeholders in the urgency hint indicator for workspaces that
+do not have any urgent windows. Enable by setting to 1.
.It Ic urgent_enabled
Enable or disable the urgency hint indicator in the status bar.
Note that many terminal emulators require an explicit setting for the bell