Issue with H5P iframe embeds shaking in Blackboard Ultra

Submitted by dkyip on Fri, 05/01/2026 - 19:04
Forums: 
Bugs in content types

Hi everyone,

I’m reaching out to see if anyone has experienced an issue with H5P iframe embeds on Blackboard Ultra Document pages.

We’re noticing that some embedded H5P content appears to “shake” or jitter, but only in Chrome and Edge. The same content works as expected in Safari and Firefox. Here's a video of the shaking: https://video.jibc.ca/media/Kaltura++Blackboard+Ultra+Shaking/0_09iaayit

We’ve identified that removing the resizer.js script stops the shaking across all browsers. However, this isn’t a viable solution for us, as the resizer is important for maintaining usability on smaller devices.

Has anyone encountered this behavior or found a workaround that allows the resizer to remain in place without causing the shaking issue?

Any insights would be appreciated.

Thanks in advance,

Dennis

otacke's picture

otacke

Mon, 05/04/2026 - 19:26

Sound like a (common) infinite resize loop, cmp. https://snordian.de/2023/09/30/what-is-it-with-h5p-and-this-resizing/

It would help tremendously if you provided the link to the content so someone could inspect the behavior live.

dkyip

Tue, 05/05/2026 - 17:33

Yeah I believe you're right regarding the infinite loop. Same object on HTML or Wordpress work fine, no issues. It must be something in Blackboard wrapping around the H5P object.

Unfortunately I can't share page from our BB without login info and our IT department will not allow non-staff/students to have an account.

Just reaching out to the community in case someone else has run into this issue and if they have a workaround.