Two observations regarding Samsung firmware on 2019 model QE55Q80R:
1. Firmware is updated automatically despite automatic updates disabled in the menu. This issue occurs in all firmware versions.
2. Recent firmware 1392 caused frequent so called "cold boots", I mean situation when TV starts with QLED logo and is very slow at the beginning. This behaviour never happened before, it was very rare to see QLED logo earlier and TV was usually responsive from the beginning. Now, with cold boot every day or so, menus and tv guide are very slow in the initial period after switching TV on. Another disadvantage of cold boot is that screen brightness is not affected by Eco sensor initially, so for example it switches on with max brighness 50 and then in the right conditions brightness is reduced slowly to 15 which is set as min in my Eco settings. So having cold boot frequently is very unpleasant to my eyes.