Bug 210009

Summary: window.innerHeight is broken in WKWebView with viewport-fit=cover
Product: WebKit Reporter: evangun2001
Component: New BugsAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: f.miguel.r.oliveira, hi, ik, schauerte, thorton, webkit-bug-importer, wenson_hsieh, xtassin
Priority: P2 Keywords: InRadar
Version: WebKit Local Build   
Hardware: iPhone / iPad   
OS: iOS 13   

Description evangun2001 2020-04-04 13:01:53 PDT 
When `viewport-fit=cover` is used in Cordova with the WKWebView plugin, `window.innerHeight` reports a wrong value.
Instead of reporting the proper window height, it reports the window height MINUS the safe areas insets.

Even a minimalistic snippet will demonstrate the issue: https://gist.github.com/louisameline/d5ae03b07db8185051346b8da55a2704

The issue happens only if the content of the page is smaller in height than the window height.
Exemple: if my iPhone window is 812px high, and the "natural height" of my page is 500, `window.innerHeight` returns 734 (= 812 - 44 top safe area inset - 34 bottom safe area inset). If my page content is 750px high, `window.innerHeight` returns 750, and if my page content overflows the window, `window.innerHeight` returns 812.

Additional notes:
- The `window.innerHeight` value is not longer false after a rotation of the screen
- The bug does not happen in Chrome, Safari, UIWebView, Ionic WKWebView, Capacitor
- It was previously brought to the Cordova team, who suggested to report it here: https://github.com/apache/cordova-plugin-wkwebview-engine/issues/108

Thanks
Comment 1 evangun2001 2020-04-04 13:05:30 PDT 
Tested on iPhone XS, iOS 13.4, Xcode 11.4, cordova-ios 5.1.1, cordova-plugin-wkwebview-engine 1.2.1
Comment 2 Radar WebKit Bug Importer 2020-04-06 22:55:17 PDT 
<rdar://problem/61378008>
Comment 3 ik 2022-03-16 08:39:44 PDT 
This also affects standalone web apps, see https://bugs.webkit.org/show_bug.cgi?id=237961