xlsclients
List client applications running on an X11 display. tldr-pages
On several platforms
Several platforms
List clients on the default display
xlsclientsIdentifyList clients on all screens
xlsclients -aIdentifyList clients with detailed information
xlsclients -lIdentifyLimit the command output length per client to a specific number of characters
xlsclients -m max_command_lengthIdentifySpecify a particular display to inspect
xlsclients -display :display_numberIdentifyList clients on remote host's display
xlsclients -display remote_host:0IdentifyDisplay version
xlsclients -versionIdentify