External subtitles for plex broken?

Hello, I’m using Infuse 7.8.3 (7.8.4964) with plex plugin connecting to my server.
I remember that Infuse can automatically detect external subtitles but is not working now.

My plex server (version 1.41.0.8994) files are like this:

movie_name
-----  movie_name.mkv
-----  movie_name.en.srt (I also tried movie_name.srt)

From plex panel I can see the external subtitles are correctly recognized, but in infuse I cannot find any external subtitles.

This also happens to iOS version, can anyone help me?