Observation on Ubuntu 18.04 : - All work good on Xorg session - Problem only affect Wayland session - Classic windows with traditional decoration (chromium, pidgin, inkscape, ...) accept middle-click action - GTK3 apps with Headerbar decoration who use CSD (Client Side Decoration) ignores middle-click - Don't know why, but Evolution 3.28.1-2 ignores middle-click too (but have traditional decoration !)
Freedesktop talk about that since December 2016 : https://lists.freedesktop.org/archives/wayland- devel/2016-December/thread.html#32028 -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to mutter in Ubuntu. https://bugs.launchpad.net/bugs/1698083 Title: Middle-click titlebar actions (like maximizing vertically) don't work in Wayland sessions To manage notifications about this bug go to: https://bugs.launchpad.net/gtk/+bug/1698083/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
