commonvoice.mozilla.org - The recording does not fully play when replayed

[softvision-oana-arbuzov]

URL: https://commonvoice.mozilla.org/en/speak

Browser / Version: Firefox 87.0
Operating System: Android
Tested Another Browser: Yes Chrome

Problem type: Something else
Description: The recording does not fully play when replayed
Steps to Reproduce:

1. Navigate to https://commonvoice.mozilla.org/en/speak
2. Speak and record the provided text.
3. Click any of the recordings.
4. Click "Replay" button.

Expected Behavior:
The recording fully plays.

Actual Behavior:
The recording plays for a few seconds, but not fully.

Notes:

1. The issue is also reproducible on mobile.
2. Video recording https://drive.google.com/file/d/1aqS4ECzW4gx1sJsjagFkAFleol5LauS1/view?usp=sharing
3. The issue is not reproducible on Chrome 88.0.4324.182
4. The issue is not reproducible on Firefox Release 85.0.2 and Firefox Daylight 85.1.3 (🦎 85.0.2-20210208133944)

Watchers:
@softvision-oana-arbuzov
@softvision-raul-bucata

View the screenshot

Browser Configuration

• None

From webcompat.com with ❤️

[denschub]

Moved this over to the commonvoice repo at common-voice/common-voice#3018 :)

[phirework]

Hey @denschub, I don't think this is a Common Voice bug. I've tested FF 87 with an isolated MediaRecorder instance from MozDevs and the same thing happens, only the first 1 - 1.5 seconds are recorded. That MozDevs code hasn't changed since 2016 (and the equivalent Common Voice recording code hasn't changed since last fall), but we started getting an increase in reports of this problem after the 87.0 release date.

In the CV repo at least it seems to be related to the size of the blob - the full recording streams fine if I call MediaRecorder.start() with a smaller max blob size (testing seems to indicate 250-300ms is the max before the assembled clip start getting truncated).

This issue does not exist on 85 or 86 and does not reoccur on Beta 88 or Nightly 89a1, so it's probably not actionable, but wanted to log it here in case that helps track down related MediaAPI bugs.

[denschub]

I checked again, and it appears to be working fine indeed. Thanks for the feedback!

[softvision-oana-arbuzov]

I can confirm it works correctly now.

Tested with:
Browser / Version: Firefox Nightly 90.0a1 (2021-05-03), Firefox Nightly 90.0a1 (🦎 90.0a1-20210503094544)
Operating System: Windows 10 Pro, Google Pixel 5 (Android 11) - 1080 x 2340 pixels, 19.5:9 ratio (~432 ppi density)