Select Opus.webm and 48000Hz ; click on play.
96000 frames will be decoded, sample is exactly 2s long.
When the audio loop, you can hear a small click.
Running this on Firefox and Chrome, no click (indicative of a short silence being played) can be heard.
I believe this is due to rdar://81002989 ; the number of frames returned is incorrect.
What we hear is a combination of the frames that should have been dropped but weren't and the frames never returned when they should have been decoded.
This got fixed already.