This could be related to OpenGL texture sizes or something similar. Unity7 (Compiz) has workarounds to avoid that limitation. And Xfce avoids it by not using hardware accelerated compositing at all (last I checked). It's not surprising if only Gnome Shell hits a problem like this...
Do you get the same bug logging in to "Ubuntu" vs "Ubuntu on Xorg"? -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1725836 Title: No more than 2 displays work simultaneously Status in Mutter: Confirmed Status in gnome-shell package in Ubuntu: Incomplete Status in mutter package in Ubuntu: Incomplete Status in xorg-server package in Ubuntu: Incomplete Bug description: I have three displays that worked fine in 17.04. Now ith 17.10 I can only use two of them. Either 1 & 2, 1& 3 or 2 2 & 3. All three seem to be properly specified in monitors.xml. The display setup scree detects all three. UBUNTU 17.10 AMD PitcairnLSB Version: core-9.20160110ubuntu5-amd64:core-9.20160110ubuntu5-noarch:security-9.20160110ubuntu5-amd64:security-9.20160110ubuntu5-noarch --- ApportVersion: 2.20.7-0ubuntu3 Architecture: amd64 CurrentDesktop: ubuntu:GNOME DisplayManager: gdm3 DistroRelease: Ubuntu 17.10 InstallationDate: Installed on 2017-02-23 (242 days ago) InstallationMedia: Ubuntu 16.10 "Yakkety Yak" - Release amd64 (20161012.2) Package: mutter PackageArchitecture: amd64 ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4 Tags: artful Uname: Linux 4.13.0-16-generic x86_64 UpgradeStatus: Upgraded to artful on 2017-10-20 (3 days ago) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/mutter/+bug/1725836/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
