Yah I think it's a bug for the cover screen. My custom gif I have also randomly disappears & whatever widget I save. I suggest reporting it if you can, they might already know about the issue or they might not but wouldn't hurt to report. I've reported it myself
Please try force stopping the app, clearing its cache and rebooting your device. If issue continues, please send us an error report to help us debug the issue. We apologize for the inconvenience and appreciate your contribution to the beta program.
