<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - resizging windows is slow, flickery and momentous." href="https://bugs.freedesktop.org/show_bug.cgi?id=81275#c9">Comment # 9</a> on <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - resizging windows is slow, flickery and momentous." href="https://bugs.freedesktop.org/show_bug.cgi?id=81275">bug 81275</a> from <a class="email" href="mailto:fourdan@xfce.org" title="Olivier Fourdan <fourdan@xfce.org>"> Olivier Fourdan</a> <pre>The flickering black border is a known issue with gnome-shell: <a href="https://bugzilla.gnome.org/show_bug.cgi?id=767212">https://bugzilla.gnome.org/show_bug.cgi?id=767212</a> I suspect this is a frame synchronisation issue between the application and Xwayland. There are actually two different variations of the sync protocol, using sync counters, one being specified as the extended window manager hints (EWMH) here: <a href="https://specifications.freedesktop.org/wm-spec/wm-spec-latest.html#idm140200472538288">https://specifications.freedesktop.org/wm-spec/wm-spec-latest.html#idm140200472538288</a> But mutter/gnome-shell goes further and uses an extended variant of this protocol referred as the "extended synchronization" by Owen here: <a href="http://fishsoup.net/misc/wm-spec-synchronization.html">http://fishsoup.net/misc/wm-spec-synchronization.html</a> gnome-shell/mutter is an X11 window manager/compositing manager and a Wayland compositor as well, when running Xwayland applications that implement either the basic or extended XSync protol as defined by Owen in the link above, the synchronisation is based on the application content which may not match the WM windows content (which are [a] separate window[s]) from the window manager). So the issue, I reckon, occurs with SSD (server side decorations), as opposed to CSD (client side decorations) applications that implement the Xsync protocol (that pretty much include most of gtk2 apps and some gtk3 apps, those using SSD and not CSD). This is pretty easy to test, can you reproduce the issue with, say, xterm? (or any basic X11 which does not implement Xsync). One last note, I am surprised you mentioned the issue occuring with weston because, afaik, weston does not implement the XSync part of the EWMH specs, and I could never reprodcue the issue with weston, so *maybe* what you saw with weston was some other problem more specific to weston.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>