When Enabling the AP, the video simply doesn’t stop at the end of each line. I’ll then click on the video to pause it manually, and the video will behave as if it is unpausing (pausing and then instantly unpausing). Hovering over the subs also doesn’t pause the video as you would expect.
The videos in Question:
Five other videos I checked did work as intended, so the bug seems to only be present on certain videos. Reloading these videos did not solve the issue.