Hi,
I have here a Screenly OSE Installation on RPi 4b (OS Buster lite Legacy).
I tried to rotate from Landscape to Portrait Mode with “display_rotate=1” but it doesn’t works.
Can anyone help me
You can do this from the web page now, with no config file editing. Anthias added screen rotation to the settings (#2882), and rotation on the Pi 4 specifically was sorted out in #2971. Choose portrait or landscape there and the screen rotates to match. Marking this as solved. If the rotation still looks off on your Pi 4, let us know and we will help.