1.9.0 - Video thumbnail refresh issue after activating video

When joining a meeting (with at least one participant already in) with the Web SDK 1.9.0, we noticed than the joiner participant video thumbnail is not showing properly when video is activated right after joining the meeting.
Please check my screenshot below, as you can see, on the left you have the instructor participant (host) who joined first, and on the right a client participant (non host) who joined after the instructor.
The client video thumbnail is not showing after activating the video.
Switching to gallery mode and then back to speaker mode solve the issue, so it seems to be a UI refresh issue.

Which version?

To Reproduce(If applicable)
Steps to reproduce the behavior:

  1. Join a zoom meeting as host with web sdk, and activate video & audio after joining
  2. join a zoom meeting as non host with web sdk, and activate video & audio after joining
  3. On the non host participant, your own video thumbnail is not working due to probably a refresh bug on the UI
  4. On the non host participant, clicking on the gallery mode and then back to the viewer mode, the thumbnail video is fixed on the non host participant.


Device (please complete the following information):

  • Device: Desktop Linux, Window, MacOs
  • OS: Does not matter
  • Browser: Chrome latest
1 Like


This is a blocker issue for us (as our customers may not know how to fix that bug by themselves by switching the view modes), so we are not going to update to 1.9.0 before this can be fixed.

Can you give us feedback on it about your findings and potential SDK version with a fix?

Thank you !

we’re experienced the same issue with the sdk v1.9.0. After switching the view mode (f.ex. to gallery view) the preview is working as expected.


This is also happening time to time when a participant deactivate the video.
The thumbnail still show that participant on other’s screen but with a frozen image instead of showing no video with the deactivated sign.
It can be fixed by switching view mode so i guess it’s the same bug, or similar one.

Our organization has also experienced this behavior since updating to 1.9.0. As other posters noted, switching to Gallery view resolves the issue.

@nvivot @alexander.brotzge @amy.moses

Thank you for raising this with us. We are looking into this (CS-3013).


We are also experiencing this issue after the upgrade to 1.9.0. Switching to gallery view resolves it - we also noticed that sharing screen would trigger the video to start as well.

Hey @erichhansen,

I’m sorry to hear you seem to be encountering this bug as well. Thank you for your input and for sharing the workaround that worked for you. We’ll be sure to update you here when we have more information.


Has this been fixed in 1.9.1 ?

If not, we are not moving from the 1.8.6 just because of that (it potentially has a too big impact on our users and the tickets they would create on our helpdesk when they face this issue)
If it has not been fixed yet, priority should be given to that bug if you want us to upgrade the version.

Hey @nvivot,

Thank you for the update. It doesn’t seem that this issue has been resolved in the latest version so I’ve reached out to our development team to see if they are able to provide a timeline.


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Hey @nvivot , @alexander.brotzge , @erichhansen , @amy.moses ,

If you are still experiencing this issue with the latest Web Client SDK 1.9.5, here is a suggestion:

Applying for and enabling the WebCodecs origin trial will fix this issue (in Chrome 90 +).

More details can be found here regarding MediaStreamTrack | https://web.dev/mediastreamtrack-insertable-media-processing/

General details about registering for OT can be found here: Origin Trials Guide for Web Developers | OriginTrials


Hi @tommy

I did not fully test yet the 1.9.5 but a coworker told me that this video thumbnail issue is fixed with the 1.9.5, without activating the WebCodecs.

About WebCodec, it was not working with 1.9.1 and provoking many lags so we did not activate it (we activated only SIMD)
We will test again WebCodec on the newer version.

1 Like

Sounds good @nvivot !

Please let me know how your testing goes. :slight_smile:


Hi Tommy,

Just to let you know that the Video Thumbnail Refresh issue is no longer happening on 1.9.5 and 1.9.6.

Regarding the WebCodecs, we tested it on 1.9.6 and it introduced a new bug during screen sharing. It is just sharing a black screen. So, we cannot upgrade our app to use WebCodecs as well. I’ll be creating a new ticket for that.


Hey @lfrancia,

Thank you for reporting this, we’ll look out for your ticket.