Currently the only option for playing back ATSC OTA recordings is for subtitles to display in white letters inside a big black rectangle.
I thought that was the only option, so I shrugged it off, but I see that GetChannels displays them as yellow letters inside a black border around each letter when playing back the exact same .TS file recorded by the Plex DVR.
This subtitle format is just as easy to read against all backgrounds and far more pleasant to look at and does not block half the screen and is more tolerated by those I am watching TV with who have no problem understanding the words being spoken and would rather not see subtitles at all.
I would love to see Plex DVR playback to display the subtitles in the same manner.
I already have YTTV (which I am trying to replace with Plex DVR) and HBOMax and FireTV and everything else set to display subtitles in the same manner.
The only three lost causes I have are:
Prime Video, Roku and Plex TV.
I made the same request of PrimeVideo and Roku ages ago, with no results so far.