border (including window title), +border pixel 1+ to use a 1-pixel border (no window title)
and +border none+ to make the client borderless.
-There is also +border toggle+ which will toggle the different border styles.
+There is also +border toggle+ which will toggle the different border styles. The
+optional pixel argument can be used to specify the border width when switching
+to the normal and pixel styles.
Note that "pixel" refers to logical pixel. On HiDPI displays, a logical pixel
may be represented by multiple physical pixels, so +pixel 1+ might not
*Syntax*:
-----------------------------------------------
-border normal|pixel [<n>]
-border none|toggle
+border normal|pixel|toggle [<n>]
+border none
# legacy syntax, equivalent to "border pixel 1"
border 1pixel