Steps to reproduce:
- Create a new post and add tags.
- Close and re-open the post.
- Go to the more menu (three dots) > Post Settings.
- Verify the tags are still there.
- Tap Tags to open the tag editor.
- Rotate the device.
Result: if you rotate the device (either from portrait to landscape or vice versa) while the tag editor is open in Post Settings, the tags are removed. (1m1s)

Tested with WPAndroid 15.1-rc-1 on Pixel 3 Android 10.