I'm currently fighting a very frustrating bug on Safari, and I'm not sure where else to turn.

It seems most elements (but not all, and I can't discern the differentiating factor) that will trigger a focus event will cause all elements on the page that are transitioned or animated to jump ~2px to the top and left. And this only occurs on the first focus event after the page loads.

It's a little annoying to see the bug, as it's in the logged-in portion of droplr.com, and I have been completely unable to distill down a simpler case on JSFiddle.

If you have/create an account and log-in, click on this edit icon for a drop:

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You'll see that on the first focus of the page, things jitter. Here's the timeline when there's a single drop on the page and I trigger focus on an offending element:

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With more drops, it's just more of the same, but it seems to max out around 40 paints. And the profiler doesn't suggest anything nefarious. Just a trip through jQuery internals.

If instead of laying elements out via a translate3d or matix3d, I simply use top and left, this bug goes away. After hours and hours of debugging this, I'm at a complete loss.

Hoping someone has seen something similar, could take a look, or could give me advice on debugging next steps.

Thanks so much!

Update: Dave Desandro suggested it was the 3d acceleration kicking in, so I tried it out with a translate instead, and sure enough, that did not cause the jitter. I have no idea why the hardware acceleration woul

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