[deanmv]

You have two options here, there is:

ShowSubtitles Toggles whether subtitles are shown or not.
NextSubtitle Change to the next subtitle language, if there is more than one.

So it would be (same buttons example as before)

Code:

<button id="18">ShowSubtitles</button>

or

Code:

<button id="18">NextSubtitle</button>