Video player does not go fullscreen and screen turns off during playback (Galaxy Z Fold6, 35.0.1) #17825

⚠️ Before posting ⚠️

• This is a bug, not a question or an enhancement.
• I've searched for similar issues and didn't find a duplicate.
• I've written a clear and descriptive title for this issue, not just "Bug" or "Crash".
• I agree to follow Nextcloud's Code of Conduct.

Steps to reproduce

1. Open the Nextcloud Android app (35.0.1).
2. Open any video file from a folder so it plays in the app’s built-in player.
3. Put the phone down on a table and don’t touch it.

Expected behaviour

• The video opens in fullscreen (immersive mode, system bars hidden).
• The screen stays on for the whole playback, as in any other video player.

Actual behaviour

• The player does not switch to fullscreen. The video stays in a non-fullscreen layout with the system bars visible.
• After the system screen timeout, the screen dims and then turns off while the video is still playing. The player doesn’t seem to keep the screen awake (e.g. no FLAG_KEEP_SCREEN_ON/ keepScreenOn) during playback.

Android version

16

Device brand and model

Samsung Galaxy Z Fold6

Stock or custom OS?

Stock

Nextcloud android app version

35.0.1

Nextcloud server version

26 Winter

Using a reverse proxy?

No

Android logs

No response

Server error logs

Additional information

Reproducible every time. Other video players on the same device stay fullscreen and keep the screen on during playback, so this seems specific to the Nextcloud in-app player.