Is there a video/movie player for Linux that
(a) has a setting for the transparency/opacity of the subtitles and
(b) can append/combine subtitles from two subtitles (e.g. SRT) files?
By "transparency/opacity of the subtitles," I do not mean that of the background rectangle for subtitles. (I don't want any background rectangle.) I want the subtitles themselves to be half see-through so they don't entirely blot out the video information.
By "append/combine" I don't mean placing one language subtitles on top and the other at the bottom of the movie screen. Both languages should be at the bottom, one language stacked atop the other.
Potplayer for Windows can do both (a) and (b) (combining multiple subtitles files is called "appending"). It seems SMPlayer can do neither, or I have not found out the how.
I would be happy to receive, as an answer, a Linux video/movie player that can do at least one of (a) and (b). Thank you.