First: this is for Android 10 which does not exist in List

SUMMARY
When I play a video on connected device the media control notification on my phone breaks the lock screen which leaves the phone unusable. Stopping media playback makes the Phone usable again. Deactivating the entry in the configuration resolves the issue.

STEPS TO REPRODUCE
1. Configure KDE Connect to show notifications on lock screen for media control of connected device
2. Start playback on a connected device
   I had a Youtube video running in Firefox
   I can even start the media playback from my phone to trigger the issue.

OBSERVED RESULT
The device gives a notification sound, the lock screen is shown even when the device is unlocked. A Notification from KDE Connects starts to appear. The screen goes black. Not even a second later I get an notification sound, the lock screen with the media playback notification is appearing and the device goes blank again. This continues until I stop media playback on the remote device.

EXPECTED RESULT
Notification appears normally.

SOFTWARE/OS VERSIONS
Android 10 on Xperia XZ2 Compact
Version 1.13.6 installed from F-Droid Store
Connected device is Fedora 31 with kde-connect-1.3.5-1.fc31 and Firefox with Plasma Integration

ADDITIONAL INFORMATION
I noticed that another notifcation is also shown about applying the device theme. Normally I see that on device startup only or after changing the theme.