When enabling VR with the HTC Vive Cosmos, the screen within the headset glitches out and moves to the lower right. The view on the monitor looks fine, and every other VR game works fine.
The issue can be momentarily fixed by either taking a steam screenshot or moving the headset out of and back in range. However, it reappears within a few seconds.
I have updated both the headset and Steam VR to beta, and have disabled theatre mode.
This issue only started when I upgraded to the Cosmos; the standard Vive had no issues.
Because of how the issue rights itself when a screenshot is taken, it is impossible to get one. However, the appearance is nearly identical to this screenshot of another issue:
Simply enabling VR mode with the HTC Cosmos causes the problem to appear.