Worldbuilding SE running slowly/choppy scrolling?

Recently I've started browsing Worldbuilding SE again. I've noticed that on my browser of choice (Safari), it runs at a very choppy pace compared to other sites in the Stack Exchange network such as Stack Overflow. Scrolling on any page feels laggy and choppy to the extent that the site becomes hard to use.

Since I didn't notice it on other Stack Exchange sites, I'd like to know if this is an issue with Safari as a browser or if it might be something specific to this Stack Exchange. If so, what would the fix be (other than switching browsers)?

Unfortunately, as far as regressions are concerned, the last time I visited Worldbuilding SE was a long time ago so I can't give a date for the last time it worked well for me.

• Hello Andrew. What OS and OS version are you using? And what device are you on? Jan 1 '19 at 1:26
• macOS 10.13.6, Safari 12.0.2. Web Inspector/Console does not report any errors or warnings with JavaScript on the site. Jan 1 '19 at 2:45
• People using Microsoft Edge reported a similar problem. worldbuilding.meta.stackexchange.com/questions/6810/… Jan 1 '19 at 17:15
• @Vincent Seems to be a little different on Safari. The problem described in that question has some similarities but does not seem to be exactly the same problem that I'm experiencing on Safari. Jan 1 '19 at 22:21
• For what it's worth, I've seen this a few times with the latest Firefox ESR. Jan 7 '19 at 4:32
• I've been having the same problem for a while now and Worldbuilding is easily the slowest site I visit regularly. I am running Safari on a late 2013 MBP 15" with discrete graphics and an i7. The problem is not present in FF and Chrome. Looking at Timelines in the Safari dev tools, there seem to be a bunch of Composite items, each consiting of 3 Paint events on an area of 647,168px^2. The duration of the Composites varies, but the average is around 60ms, which looks kind of long. Apr 10 '19 at 20:13
• I see this too, with a 2015 MBP 15" i7, running Safari on 10.14.5. If I disable the background-attachment: fixed,scroll,scroll rule in the CSS for the body element, scrolling is nice and smooth. Jun 19 '19 at 20:20
• Nice to see that a potential cause has been isolated. Jun 19 '19 at 21:06

This problem still exists and finally got under my skin enough for me to come to meta and see if anyone else has it.

I even have the problem on this meta.

Safari 14.0.3, macOS Big Sur 11.2.2. But I have had this problem since a very long time (maybe since it left beta?), my activity on worldbuilding was just too low to care.

I do not have this problem on any other stackexchange site.

OP has described the issue perfectly: choppy, laggy scrolling. It's very unpleasant to use. And if the fix is as simple as pointed out in a comment:

If I disable the background-attachment: fixed,scroll,scroll rule in the CSS for the body element, scrolling is nice and smooth

Then I am a bit upset it has not been fixed yet.

I disabled the

background-attachment: var(--theme-background-attachment);


rule and that similarly solves the issue.

• Yep, after two years it's still choppy. Thanks for new alternative solution! Mar 8 at 3:09