Actually, this seems more like a support request since there's no real information here. Since support requests are not appropriate for a bug tracker, this is invalid. Additionally, this is an ancient bug, and newer versions of Blender may have this fixed.
** Changed in: blender (Ubuntu) Status: Incomplete => Invalid -- You received this bug notification because you are a member of Ubuntu Studio Bugs, which is subscribed to blender in Ubuntu. Matching subscriptions: ubuntustudio-bugs: blender https://bugs.launchpad.net/bugs/1806772 Title: flashing screen Status in blender package in Ubuntu: Invalid Bug description: Flashing screen in window mode. This not happen when's fullscreen. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: blender 2.76.b+dfsg0-3build1 ProcVersionSignature: Ubuntu 4.4.0-140.166-generic 4.4.162 Uname: Linux 4.4.0-140-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.18 Architecture: amd64 Date: Tue Dec 4 20:02:48 2018 InstallationDate: Installed on 2017-01-30 (672 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) SourcePackage: blender UpgradeStatus: Upgraded to xenial on 2018-08-23 (103 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/blender/+bug/1806772/+subscriptions -- Mailing list: https://launchpad.net/~ubuntustudio-bugs Post to : ubuntustudio-bugs@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntustudio-bugs More help : https://help.launchpad.net/ListHelp