Server Version#: QNAP v.5.1.6 / Plex Server v.1.440.2
Player Version#: Tested in three players: iOS 17.4.1 (iPhone12), OSX 11.7.10 (MacBook Pro), Chromecast with the same results.
Took a portrait picture. Verified that it does contain in its metadata the orientation information, using from OSX Terminal the commands:
orientation=$(exiftool -n -Orientation -S -s "IMG_0225.oriented.png")
echo $orientation
The last command reported 6, which according to ChatGPT should be “Rotated 90 degrees clockwise”.
Placed the photo in a new folder inside the Photos folder of my Plex Server.
Displayed the photo from all three client devices listed above: it is displayed as landscape.
Any feedback will be appeciated.