Black background appears briefly before window gets drawn
Submitted by mrb..@..il.com
Created attachment 302400 application startup video
When an application is started, a black background is drawn first, before the application's window content appears.
This is only happening when I'm not using a compositor. If compositing is turned on, all the windows get drawn nicely (without the black background appearing).
I'm using GNOME applications outside of GNOME; I tested this with Openbox/Compton and with Xfce4's window manager/compositor and they both had the issue. It's also only happening with GTK3+ applications, GTK2 and applications using other toolkits get drawn without the black background.
I attached a short video clip which demonstrates it.
Attachment 302400, "application startup video":