[bug] Multiple caption tracks for the same language are not available

[emmitrin]

I have some videos which include several options of subtitles for the same language (e.g. "English", "English extended" and so on).

I've added them as multiple track tags with the same srclang; Plyr renders the list of captions correctly, but when I select the second/third/... caption track it just picks the first one instead.

I haven't looked at the Plyr sources yet, but I guess it stores the picked caption track only based on srclang so this may lead to inability to have multiple tracks under the same srclang.

With pure HTML5 video the captions are behaving correctly.

Expected behaviour

Able to select one of the several English captions

Actual behaviour

Only the first English caption track will be selected even if you click on the second one

Steps to reproduce

1. Open the pen below
2. Go to Player Settings->Captions and select English (extended)
3. English will be picked instead

Link to where the bug is happening

https://codepen.io/emmitrin/pen/dyjjYKr