For the record, this just happened to me on a *fresh* install of Ubuntu 18.04.
The first thing I did after system installed months ago was to install Unity from repositories (and set lightdm as the default greeter). Unity may not be the default anymore in 18.04 but it runs and looks great. Today I needed to test Gnome Shell. So I logged out, and in the greeter selected "Ubuntu (default)" instead of pre-selected "Ubuntu (Unity)". And that *insane* zoom up happened. Same as described by OP. Logging out and back into Unity everything is OK. Also tried "Ubuntu (default on Wayland)" and same super zoom -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-shell in Ubuntu. https://bugs.launchpad.net/bugs/1705156 Title: gnome-shell interface shows up extremely scaled up Status in gnome-shell package in Ubuntu: Invalid Bug description: Trying the gnome session, the login process and gdm screen work perfectly, but then in gnome shell, I get a very scaled up interface that is completely unusable. Even the mouse cursor size is like 1/4 of the screen's size Instead, logging back to Unity, the interface shows up with the correct, usual scaling dimensions ProblemType: Bug DistroRelease: Ubuntu 17.10 Package: gnome-shell 3.24.2-0ubuntu7 ProcVersionSignature: Ubuntu 4.11.0-10.15-generic 4.11.8 Uname: Linux 4.11.0-10-generic x86_64 ApportVersion: 2.20.5-0ubuntu5 Architecture: amd64 CurrentDesktop: Unity:Unity7 Date: Wed Jul 19 09:23:06 2017 DisplayManager: gdm3 EcryptfsInUse: Yes GsettingsChanges: b'org.gnome.shell' b'favorite-apps' b"['chromium-browser.desktop', 'org.gnome.Nautilus.desktop', 'org.gnome.Terminal.desktop', 'update-manager.desktop', 'skypeforlinux.desktop', 'slack.desktop', 'virtualbox.desktop', 'popcorn-time.desktop', 'chrome-hmjkmjkepdijhoojdojkdfohbdgmmhki-Profile_2.desktop', 'pcgarage_py.desktop']" b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'" b'org.gnome.desktop.interface' b'scaling-factor' b'uint32 1' InstallationDate: Installed on 2012-11-25 (1696 days ago) InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Alpha amd64 (20120627) SourcePackage: gnome-shell UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1705156/+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
