My ereader automatically also enabled lockscreen rotation when home screen rotation is enabled. I also saw that some Samsung phones have a separate toggle for this: https://www.youtube.com/watch?v=JxLZ6yZAJ3Q
On my FP4 (stock OS, build FP4.QREL.15.16.1), it never rotates the lockscreen. I also don’t see the following option at all:
Is it possible?
Maybe you should use the hardware test tool (dial *#*#2886#*#*) to check if the rotation sensor is working.
@Wallby I think you may be confusing two completely different things,
(A) “lockscreen* rotation”
by which, I think, you mean “rotating the content of the screen of the phone when the phone is locked”, and
(B) “lock screen rotation”
as used in the linked topic, meaning “prevent the screen content from rotating when the phone is rotated”.
I didn’t reply when the question was initially asked because I was not sure of the answer, and I’m still not quite sure, but I rather think that it is not possible to have the lockscreen (sense A) rotate so as to display its content in landscape orientation when the phone is locked. At any rate I don’t know how that would be done and I have never seen it done.
However, the screensaver, which is shown when the phone is charging, does use the orientation of the app that was displayed at the moment the screensaver was triggered.