Does Plex support forced subtitles or not?

Recently I have been watching a show which was produced in a foreign language but has an excellent English dub. The DVD release uses a forced (or otherwise default) subtitle track for a few random elements which could not be conveyed in the audio track, like visible text that you are expected to be able to read.

I tried using MKVToolNix to mark these subtitles as default and/or forced. Plex notices the change and updates the subtitle name, but still does not display them by default; I have to manually turn on subtitles for every single episode, pausing the video for 5 seconds every time. This happens even if “Automatically select audio and subtitle tracks” is checked.

This support page talks about this issue, but annoyingly it does not specify what happens in the typical case, when subtitle preferences have not been changed. And I don’t want to change my subtitle setting anyway, because neither option seems appropriate. I could set them to display for foreign language audio only, but that obviously wouldn’t help me here because the audio is in English. The always enabled setting would force me to disable subtitles everywhere else, so it just inverts the problem.

Is there any way to get Plex to always display only forced subtitles?

@telion said:
I could set them to display for foreign language audio only, but that obviously wouldn’t help me here because the audio is in English.

You are misunderstanding it.

Your ‘forced’ subtitle needs to be marked as ‘english’, not as the language from where it translates the text.
So in your file:
audio track = english
subtitle track= english, forced

Set the options in the Language preferences as follows
Subtitles: ‘foreign language audio only’
set both preferred audio and subtitle language to ‘english’.
Don’t forget to fill the checkbox ‘Automatically select audio and subtitle tracks’.

This will automatically activate a subtitle track that is marked as english and forced.

Do keep in mind that the automatic selection will only work on videos, where the audio and subtitle selectors have not been touched by you before.

Thank you! I can’t believe it was that simple. I had actually tried the “foreign language audio only” option before, but I must have tested on an episode I had already viewed.