I'm not familiar with the -fd option myself, but confirm it can be made to crash:
Xmir :1 -fd 9999 ** Changed in: xorg-server (Ubuntu) Status: New => Confirmed ** Changed in: xorg-server (Ubuntu) Importance: Undecided => High -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1675481 Title: Xmir crashes when using the '-fd' option To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1675481/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp