1668113 - BlackBoard course list not rendering properly for students using Firefox 81.0

Status: VERIFIED DUPLICATE of bug 1665447

(Core :: Layout, defect)

Description

[Jonas Hunziker]

Attachment: Blank boxes should contain text and be clickable.

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:81.0) Gecko/20100101 Firefox/81.0

Steps to reproduce:

Access https://elearning.kctcs.edu/ultra/course after login with KCTCS account.

Actual results:

Each course gets a box but only some of the boxes populate in Firefox 81. Worked fine in Firefox 80.1 and ESR 78.3.

Expected results:

All the boxes populate and are clickable so that students can access their courses.

Comment 1

[Jonas Hunziker]

I narrowed it down, using mozregression, to this change: https://bugzilla.mozilla.org/show_bug.cgi?id=1581876

We use ESR on campus but students tend to use the latest RR release on their personal machines, so this is going to cause some problems. Let me know how I can assist.

Comment 2

[Jonas Hunziker]

Attachment: Desired look where boxes are populated with text and clickable.

Comment 3

[Ryan VanderMeulen [:RyanVM]]

Is there a live site we can use to test and debug this?

Comment 4

[Jonas Hunziker]

(In reply to Ryan VanderMeulen [:RyanVM] from comment #3)

Is there a live site we can use to test and debug this?

Ryan, I'm checking to see if there is a way. AFAIK, all our BlackBoard logins are process-driven domain accounts :| Would a remote access session work in a pinch?

Comment 5

[Jonas Hunziker]

(In reply to Ryan VanderMeulen [:RyanVM] from comment #3)

Is there a live site we can use to test and debug this?

Our Learning Systems Administrator just made the following suggestion:
"Mozilla could sign up for Bb course site access. https://www.coursesites.com/ then create five courses to replicate. This site is provided by Bb, free to use (up to five courses) and is on the same build and version as our production instance."

But I'm still going to look for a way to give you access to our BlackBoard shell.

Comment 6

[Karl Dubost💡 :karlcow]

So going to the blackboard site.
https://help.blackboard.com/Learn/Administrator/Hosting/Release_Notes/Browser_Support

Firefox 57+ is supported according to this page.

So there could be a bug they are unaware of.

Comment 7

[Karl Dubost💡 :karlcow]

https://github.com/blackboard
https://github.com/orgs/blackboard/people

I will try to ping them on the webcompat issue.

Comment 8

[Karl Dubost💡 :karlcow]

Let's see if we can have a better idea through contacting them, and if with people at Blackboard we identify a bug in Firefox, we can come back to Core.

Comment 9

[Emilio Cobos Álvarez (:emilio)]

There's one other IntersectionObserver related issue that is on my queue (bug 1665447) which could be related, but it was all pre-existing as well... If I can help diagnose this somehow let me know.

Comment 10

[Wade]

I'm a Blackboard admin at my institution, happy to help if I can. I've put in a support request with Blackboard and referenced this bug.

I can confirm that IntersectionObserver is used by the Blackboard Ultra interface (though it's all minified JS, and generally very indirect, so it's hard to follow). I haven't identified a workaround yet - though I could write a GreaseMonkey script or something to just list out the course URLs, or possibly to trigger whatever the IntersectionObserver is failing to trigger. But as Blackboard Learn is SaaS there's not a whole lot we can do to modify its behaviour server-side.

Comment 11

[Wade]

As a workaround, I've written a GreaseMonkey userscript that forces Learn to use a polyfill (they include https://github.com/w3c/IntersectionObserver/tree/master/polyfill) instead of the broken API.

https://gist.github.com/wade-tattersall/39044f0cdbe3aefeedaefaac2b71d8f2

I'd say this confirms that it's IntersectionObserver at fault.

Comment 12

[Emilio Cobos Álvarez (:emilio)]

I wonder if any of the affected people could try a build from here when they're available, which has a fix for bug 1665447: https://treeherder.mozilla.org/#/jobs?repo=try&revision=6825a0fd201a0580ffece443b32b5bde9b1edb21

(You can click on the "B" button for your platform, the download the target.{dmg,zip,tar.gz} file from the "artifacts" tab)

Comment 13

[Jonas Hunziker]

(In reply to Emilio Cobos Álvarez (:emilio) from comment #12)

I wonder if any of the affected people could try a build from here when they're available, which has a fix for bug 1665447: https://treeherder.mozilla.org/#/jobs?repo=try&revision=6825a0fd201a0580ffece443b32b5bde9b1edb21

(You can click on the "B" button for your platform, the download the target.{dmg,zip,tar.gz} file from the "artifacts" tab)

I just tested the x64 Windows build and it works for me!!

Comment 14

[Jonas Hunziker]

Attachment: Working with new nightly.

Comment 15

[Wade]

Yep, the above build works for me too (Win64).

Comment 16

[Julien Cristau [:jcristau]]

Given comments 13 and 15 I guess we can call this fixed by bug 1665447.

Comment 17

[Ryan VanderMeulen [:RyanVM]]

This should be fixed in Firefox 81.0.1 being targeted to ship tomorrow. Thanks for the report and responsiveness, Jonas!

Comment 18

[Jonas Hunziker]

(In reply to Ryan VanderMeulen [:RyanVM] from comment #17)

This should be fixed in Firefox 81.0.1 being targeted to ship tomorrow. Thanks for the report and responsiveness, Jonas!

My pleasure. Mozregression is a great tool, and thanks to you guys for being responsive as well!

Comment 19

[Ryan VanderMeulen [:RyanVM]]

Jonas and Wade, Firefox 81.0.1 is now live though you may need to manually check for updates to receive it right away (we throttle updates a bit initially). Can you confirm that things are working for you now?

Comment 20

[Jonas Hunziker]

Attachment: Working on 81.0.1

Can confirm that it is working for me in 81.0.1. Thanks again for the quick fix!

Comment 21

[Ryan VanderMeulen [:RyanVM]]

Thanks again for the quick testing. Sounds like we can call this bug verified.