Bug 186549

Summary: Scrolling over fixed elements to top when scroll position is 0 will trigger body scroll
Product: WebKit Reporter: Daniel Husar <dano.husar>
Component: CSSAssignee: Nobody <webkit-unassigned>
Status: RESOLVED WORKSFORME    
Severity: Normal CC: bfulgham, hi, simon.fraser, wenson_hsieh
Priority: P2    
Version: Safari 11   
Hardware: iPhone / iPad   
OS: iOS 11   
Attachments:
Description Flags
Scroll animation
none
Demo page none

Description Daniel Husar 2018-06-11 16:43:18 PDT
Created attachment 342481 [details]
Scroll animation

When you are inside fixed element, and scroll position is at 0, scrolling to top will actually trigger scroll of the body, and while that scroll animation has not finished you can't interact with fixed element.
This can be confusing when fixed element takes full body size, so the whole screen is locked and you dont know why.

See the attached animation for better idea whats going on.
Comment 1 Daniel Husar 2018-06-11 16:44:12 PDT
Created attachment 342484 [details]
Demo page
Comment 2 Simon Fraser (smfr) 2018-06-13 16:37:48 PDT
This is because UIKit prevents scrolling of the page when rubber-banding is in progress. It's not a great user experience.
Comment 3 jonjohnjohnson 2018-12-19 10:59:33 PST
dano.husar@gmail.com these links show a workaround to your problem

https://bugs.webkit.org/attachment.cgi?id=356972
https://vault.jonjohnjohnson.com/examples/cssripstop/
Comment 4 Brent Fulgham 2022-07-15 13:21:22 PDT
I don't think there is any action planned for this use case at present.