xwininfo

Display information about windows. See also: xprop, xkill. More information: https://www.x.org/releases/current/doc/man/man1/xwininfo.1.xhtml.

• Display a cursor to select a window to display its attributes (id, name, size, position, …):

xwininfo

• Display the tree of all windows:

xwininfo -tree -root

• Display the attributes of a window with a specific ID:

xwininfo -id id

• Display the attributes of a window with a specific name:

xwininfo -name name

• Display the ID of a window searching by name:

xwininfo -tree -root | grep keyword | head -1 | perl -ne 'print $1 if /(0x[\da-f]+)/ig;'