Live-video captions (CC) break when font is not 100% (emulated)

[stsvilik]

Description

When using emulated closed captions on a live video and using "caption settings" to set font above or below 100%, captions collapse to the bottom of the screen and start appearing one on top of the other.

Example can be found here.

Steps to reproduce

1. Wait until a live video is playing (ignore ad or intermission)
2. Hover over "CC" and turn on caption
3. Hover over "CC" again and click on "Gear" icon to show settings
4. Change font size in the drop-down to anything other than 100%

Results

Expected

Captions to appear in the designated parts of the screen with just font size changing to what was set in the settings.

Actual

All captions appear on the bottom, overlaying one another as they come in.

Error output

No errors.

versions

videojs

5.12.6 (earlier versions have it too)

browsers

all

OSes

MacOS/Windows

plugins

are any videojs plugins being used on the page? If so, please list them below.
Hlsjs and several custom plugins.