Setting Page Disappears On Screen Rotation

Expected behavior

On changing the orientation of the screen I should be able to remain on the same page of the screen.

Actual behavior

When I change the screen orientation of the screen the settings page disappears.

How to reproduce

1. Install the app from F-droid.
   
2. Launch the app in potrait mode.
   
3. Click in the green upward arrow on bottom right corner of the app and click on settings icon.
   
4. Now change the orientation of the screen to Landscape mode.
   
   The settings page will disappear on screen rotation.
   

• App Version: 0.7.5
  
• Device: Samsung Galaxy J5
  
• Operating System: Android 6.0.1

Recording Of The Bug

Here's the video recording of the bug.