Sometimes such black regions appears on screen
black_square.png (image/png), 16.14 KB, created by Dmitry on 2011-07-06 14:25:20 UTC
Creator: Dmitry
Created: 2011-07-06 14:25:20 UTC
Size: 16.14 KB
Actions: View
Attachments on bug 22324: 48837

Use of services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.