HLS player in Fabric browser does not always show the label for captions

[elv-marc]

There is an intermittent behavior, which sometimes goes away after a few seconds or when reloading and sometimes does not.
The labels for the caption do not always show. Or sometimes, some are missing:

Screen shot taken on object iq__2zDwitJeNXxQMg9KKFBfaaWDXTMN

[elv-zenia]

Leaving this open as it is an intermittent issue. Noting that I was not able to reproduce in Chrome or Firefox with and without network throttling.