While the WebView is freezing the CPU usage is 30% (on Pixel)..

I can't reproduce the specific issue you refer to without having an account. It seems like your FAQ also uses a webview. Does the issue also reproduce for you if you interact with the FAQ page?

Just create a user account. 
Menu -> Login/Register (take a email and a password you like).
In the basket you are able to remove the event ticket ;-)

Thank you for providing more feedback. Adding requester "tobiasjs@chromium.org" to the cc list and removing "Needs-Feedback" label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The attached trace shows your app spending 11 seconds executing a single javascript call.

Generally it looks like the leaf stack frame is xhr.onload from https://www.eventim.de/obj/checkout/scripts/vendor.492a976b.js:6:31562 - although it's clearly being called multiple times. There are multiple trace events for V8 code compilation without the underlying V8.Execute finishing.

Deleted: trace_eventim.json 7.3 MB

trace_eventim.json 7.3 MB View Download

Thanks Tobias for the analysis.
We try to understand what the problem is.

I have this observation :
- Work fine with Android < 7
- Problem only with Android 7 (Nexus 6, 5, 5x, Samsung)
- Seems to work on Android 8 (only one test phone)

This observation let me suppose there is a problem in Android 7 with WebView and Chrom integration.

I have read that since Android 7 Chrom is used instead of the Android System WebView.

Is there a way to install the Android Web View on Android 7 ?
PlayStore didn't install it. I like to switch to Android WebView to check if this the problem.
Regards
Stephan

Disable Chrome, and it will switch to WebView.

However, Chrome and WebView use the exact same code to implement the WebView functionality - if they are the same version, they behave identically. It's just a different way to deliver the same code to devices to save update size, it doesn't affect how web rendering behaves.

It looks like you should have a look into the xhr.onload call as per comment #6,  skseventim@ does that help?

Not really.
Our Web-Team haven't found the look for the xhr.onload. 
Is it possible to you to describe use how you find the xhr.onload look ?

I think to isolate the problem we need the url.

I am still wondering why this problem is only on Android 7/7.1
Is the task / threading between an App and the Croce-engine different on Android 7.x ?
I ask this because the App is complete frozen for 10s.

In a real Chrome-Browser on Android 7.x we don't have the problem, it occur only in the Android WebView.

Regards
Stephan

I think you do actually have a problem in N as well; tracing shows the same block of time in V8.Execute. It's just that it's hidden during the time that a CSS-animated spinner is showing, which gives the perception of liveliness. CSS animations will continue even if long running JS has blocked the main thread.

I think the question might be: why does the spinner show/stick around on N, and not on O?

Can we still reproduce this issue?

Tried on below device with OS/webview, Sorry no luck in reproducing the bug, Only i see the error in console (no issue in scrolling or freezing)

Nexus 5x/N2G48H and Samsung S8/NRD90M
Webview: 62.0.3202.84 and chrome beta/webview : 63.0.3239.41


Note:-  skseventim@,

1. What is the Android version on your device/model/webview versions
2. Can you possible attach a video/bugreport/logcat, Thanks

--------
TypeError: element.appendTo is not a function
    at Object.link (https://www.eventim.de/obj/checkout/scripts/scriptsApp.f55f9bca.js:12:5553)
    at https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:4:31246
    at invokeLinkFn (https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:7:8917)
    at nodeLinkFn (https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:6:23001)
    at https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:7:4150
    at processQueue (https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:8:27836)
    at https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:8:28103
    at Scope.$eval (https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:9:9499)
    at Scope.$digest (https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:9:7188)
    at Scope.$apply (https://www.eventim.de/obj/checkout/scripts/vendor.79e5b045.js:9:9925) <div class="modal" ng-show="show" data-qa="modal-component">
--------------

Hi,
we made the decision to remove the script from our application which made an long running call and try to find a other solution.
The impact is to wasteful for our customer.

Our Web-Team is still astonished why this block the compleat WebView. 
More mysterious is why this happens only on Android 7 devices ?
On Android 4,5,6 and 8 there is no problem.

Regards
Stephan

Marking as won't fix since skseventim@'s team found a workaround. Please re-open if that's not the case.