FFmpeg Live Stream Forced Subtitles

I’m working with live streaming sources and need a clear, repeatable way to inject a subtitle track as “forced” so that compatible players display it by default without user interaction.

I already tested 2bit dvb it shows but need to manual select.

Used already multiple.options
Cc608+708 closed captions
Sei nal mpt sdt side injection

It needs show up all al tyoe players default like ibo player tivimate xciptv gse smart smarters pro