I added some code to a page which hosted a video on hubspot which went something along these lines (You will have to upload both the video and a vtt file):
document.addEventListener(“DOMContentLoaded”,function(e){
track = document.createElement(“track”);
track.kind = “captions”;
track.label = “English”;
track.srclang = “en”;
track.src=“/video-track.vtt”; // Will be whereever you upload it
$(“#player”).append(track); // Appending it to the Video player (using ID)
track.addEventListener(“load”, function() {
this.mode = “showing”;
video.textTracks[0].mode = “showing”;
});
});
I added this as a script in the footer of the page. Might help someone else.