1535005 - [webvtt] html5 video captions doesn't disappear after seeking back to a position with an other caption

Status: VERIFIED FIXED

(Core :: Audio/Video: Playback, defect, P2)

Description

[[e-mail]]

Attachment: bug.jpg

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:67.0) Gecko/20100101 Firefox/67.0

Steps to reproduce:

1. play video http://iandevlin.github.io/mdn/video-player-with-captions/
2. seek to a position ahead from the [Test] of the start until you reach another subtitle
3. seek back to the start while the other subtitle is being displayed

Actual results:

Captions stack instead of replacing.

Expected results:

The bug is not present in Firefox stable 65.

Comment 1

[Alastor Wu [:alwu]]

The issue in comment0 has no longer occur, but now I have found a similar issue on this site [1]. The caption didn't disappear after seeking.

[1] https://alastor0325.github.io/htmltests/webvtt/webvtt_scaled_video.html

Comment 2

[Alastor Wu [:alwu]]

Attachment: Bug 1535005 - part1 : no need to update 'mLastTimeMarchesOnCalled' in 'DidSeek()'

mLastTimeMarchesOnCalled is used to record last time we run TimeMarchOn(), so there is no need to upate it on DidSeek().

Comment 3

[Alastor Wu [:alwu]]

Attachment: Bug 1535005 - part2 : add test.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2885da69f0f3
part1 : no need to update 'mLastTimeMarchesOnCalled' in 'DidSeek()' r=jya
https://hg.mozilla.org/integration/autoland/rev/f188012d248d
part2 : add test. r=jya

Comment 5

[Cristian Brindusan [:cbrindusan]]

https://hg.mozilla.org/mozilla-central/rev/2885da69f0f3
https://hg.mozilla.org/mozilla-central/rev/f188012d248d

Comment 6

[Alin Ilea, Desktop Test Engineering]

Hi,

Reproduced the issue using Firefox 67.0a1 (20190313215409) on Windows 10.
The issue is verified using Firefox 68.0b13 (20190624133534) and Firefox 69.0a1 (20190626215508) on Windows 10 and Mac OS 10.14.

In latest nightly 69.0a1 (20190626215508) is another problem now, subtitle is displayed twice(see attachment below).
The issue occurs just with english subtitle.
Nightly 69.0a1 Build ID: 20190525093913 is first known bad build.
Pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=5d3e1ea7769357bce7297b83be3863034bcf656e&tochange=edbf8267dd4f5a786ae660ff9e2fe890cf74c48e

@Alastor Wu, should I log a new bug for this or do you know something related to this issue?

Thanks.

Comment 7

[Alin Ilea, Desktop Test Engineering]

Attachment: Subtitle.png

Comment 8

[Alastor Wu [:alwu]]

Thank you for this finding, I've filed bug1562021 for it.