Elements width position:fixed disappears (flickering) when a long content is scrolling and appears again when the scroll is stoped.
B - Steps to Reproduce:
1) Create a simple html page into a cordova proyect (for example)
2) Put a div on the top and another on the buttom width "position:fixed" atribute. Include also a long text to make posible scroll it.
I use for my test this simple estructure: http://www.oscarabilleira.com/test_ios/index.php, just copy the source code and create a html file in a cordova proyect for example.
3) When scrolls the text into the webkit the "fixed elements" disappears until the scroll is finished, only if there's a long content to scroll, like in the example. In other situations (randomly) the "flickering efect" can be shown even with a short content to scroll.
C- Expected Results:
When scroll the content the elements with "position:fixed" tag must be shown all the time even when the content is scrolled.
D- Build Date & Hardware:
After update to iOS 11 and actually with iOS 11.0.2
Tested iphone 7, iphone 7 plus and ipad air 2.
Doesn't Occur using iOS 10.x.x or earlier.
E- Additional Information:
The same like in this old bug
Does this happen with the WKWebView version of Cordova (http://blog.ionic.io/cordova-ios-performance-improvements-drop-in-speed-with-wkwebview/)?
I have tested and using WKWebView works fine
I can reproduce. Investigating.
Ah, we only call GraphicsLayer::setIsViewportConstrained() in the WKWebView code path, for coordinated scrolling.
Created attachment 326420 [details]
Comment on attachment 326420 [details]
Clearing flags on attachment: 326420
Committed r224617: <https://trac.webkit.org/changeset/224617>
All reviewed patches have been landed. Closing bug.
This has been merged, but I'm guessing it missed the cut-off date for inclusion in iOS 11.2 because the issue still exists there