1372609 - Intersection Observer page auto-scrolls to embedded iframe on load

Status: RESOLVED WONTFIX

(Developer Documentation Graveyard :: General, defect)

Description

[Alex Gibson [:agibson]]

User Agent: "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:56.0) Gecko/20100101 Firefox/56.0"
BuildID: "20170613030203"

STR:

Open: https://developer.mozilla.org/en-US/docs/Web/API/Intersection_Observer_API

Expected results:

Once the page loads I should be able to start reading the document.

Actual results:

The page jumps straight down to the embedded CodePen, and I have to scroll all the way back up again.

It looks like it might be an issue with JS in the CodePen itself, calling `scrollIntoView` on `.wrapper`.

Comment 1

[Eric Shepherd [:sheppy]]

I'll see what I can do.

Comment 2

[Eric Shepherd [:sheppy]]

It looks like this only happens in Chrome. I'll investigate further.

Comment 3

[Alex Gibson [:agibson]]

(In reply to Eric Shepherd [:sheppy] from comment #2)
> It looks like this only happens in Chrome. I'll investigate further.

It happens in both Chrome and Firefox Nightly for me. You may just need to use a browser that supports Intersection Observer API to trigger the right code path.

Comment 4

[Eric Shepherd [:sheppy]]

Actually happens in Firefox too, yeah. I've changed the code sample to scroll by getting the top of the first element in the wrapper and setting scrollTop based on that.

Comment 5

[Alex Gibson [:agibson]]

(In reply to Eric Shepherd [:sheppy] from comment #4)
> Actually happens in Firefox too, yeah. I've changed the code sample to
> scroll by getting the top of the first element in the wrapper and setting
> scrollTop based on that.

Hmm, I can confirm that the page no longer jumps on load, but now when I scroll down to the CodePen it doesn't show? (actually, it seems to be scrolled way out of view within its container, so it just appears invisible).

Comment 6

[BMO Automation]

MDN Web Docs' bug reporting has now moved to GitHub. From now on, please file content bugs at https://github.com/mdn/sprints/issues/ and platform bugs at https://github.com/mdn/kuma/issues/.