It's only certain characters that are sometimes corrupt. So it's the typography renderer at fault and not the shell.
Here's a pair of screenshots showing the glyph '4' is corrupt for me today, and what it looks like when the clock changes from '11:43' to '11:44'. ** Attachment added: "corrupt_clock_1143-1144.png" https://bugs.launchpad.net/ubuntu/+source/unity8/+bug/1583088/+attachment/4668473/+files/corrupt_clock_1143-1144.png -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unity8 in Ubuntu. https://bugs.launchpad.net/bugs/1583088 Title: Randomly corrupt characters in text rendering, mainly in Unity8 window titlebars Status in qtmir package in Ubuntu: New Status in unity8 package in Ubuntu: New Bug description: Corrupted characters in text rendering, mainly in Unity8 window titlebars. I think this is a new issue. It only started happening (on xenial desktop) in the past month or two. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qtmir/+bug/1583088/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp