To be absolutely sure you would need to: 1. Convert the display's EDID into binary from hex:
00ffffffffffff004c2d090501000000 30120103801009780aee91a3544c9926 0f5054bdef80714f8100814081809500 950fb3000101023a801871382d40582c 4500a05a0000001e662150b051001b30 40703600a05a0000001e000000fd0018 4b1a5117000a202020202020000000fc 0053414d53554e470a2020202020016f 020327f14b901f041305140312202122 2309070783010000e2000fe305030167 030c001000b82d011d007251d01e206e 285500a05a0000001e011d00bc52d01e 20b8285540a05a0000001e011d801871 1c1620582c2500a05a0000009e011d80 d0721c1620102c2580a05a0000009e00 0000000000000000000000000000001d 2. Use an EDID decoding tool to verify it yourself. Some are available in the Ubuntu archive, but also you can google for online EDID decoders. ** No longer affects: xrandr (Ubuntu) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to mutter in Ubuntu. https://bugs.launchpad.net/bugs/1792167 Title: Display size detected incorrectly Status in mutter package in Ubuntu: Invalid Status in qtbase-opensource-src package in Ubuntu: Invalid Bug description: My external monitor is detected as 7" although it is 32". All applications which use Qt auto scaling have huge controls! It seems like many users have the same problem (https://ubuntuforums.org/showthread.php?t=2390362) and thus disable Qt auto scaling. I think the solution should be to fix the size detection instead. It seems not related to the display server, compositor or window manager since the problem appeared in Ubuntu 17.04 (Mir, Unity) as well es 18.04 (Mutter, Gnome). I tried it with both Wayland and X (on Wayland). Further, it seems not related to graphics driver, since I personally use the open source driver with my internal Intel card, whereas someone else uses a proprietary Nvidia driver (https://askubuntu.com/q/1066879/206608). If it is in the wrong category, please move it / add the corresponding packages. If you need any further information to tackle the problem, just tell me! --- ProblemType: Bug ApportVersion: 2.20.9-0ubuntu7.3 Architecture: amd64 CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 18.04 InstallationDate: Installed on 2017-09-05 (372 days ago) InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412) Package: qtbase-opensource-src PackageArchitecture: amd64 Tags: bionic Uname: Linux 4.18.7-041807-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom davfs2 dip docker lpadmin plugdev sambashare sudo vboxusers video voice _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1792167/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp