I'm seeing something similar on Bionic when using the Communitheme on Wayland session, where the scrollbar also goes past the bottom of the window. It does not show up when using Xorg. I think the problem also appears under the Ambiance theme on Wayland, but I do not have a screenshot immediately available demonstrating this. The severity of the problem seems to change depending on the theme used.
(I originally reported my issue here: https://github.com/Ubuntu/gtk- communitheme/issues/199) ** Bug watch added: github.com/Ubuntu/gtk-communitheme/issues #199 https://github.com/Ubuntu/gtk-communitheme/issues/199 ** Attachment added: "Communitheme Terminal scrollbar past window edge.png" https://bugs.launchpad.net/ubuntu/+source/gnome-terminal/+bug/1720651/+attachment/5064387/+files/Communitheme%20Terminal%20scrollbar%20past%20window%20edge.png -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-terminal in Ubuntu. https://bugs.launchpad.net/bugs/1720651 Title: gnome-terminal: Extra pixel line to right of scrollbar with wayland sesssion Status in gnome-terminal package in Ubuntu: Confirmed Bug description: Scrollbar drawing broken, with light theme variant on wayland session. See attached screenshot (white line right of scrollbar). To fix this you should remove some unity-compatible patch. Ubuntu 17.10, gnome-terminal-3.24.2-0ubuntu4 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-terminal/+bug/1720651/+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