Browser stop redrawing on resize.

[ekalchev]

Bug Report

• What version of the product are you using?
  65

• What architecture x86 or x64?
  x86

• On what operating system?

  • Win10

• Are you using WinForms, WPF or OffScreen?
  WPF + Winforms control

• What steps will reproduce the problem?
  I provided reproducible sample application https://ufile.io/jfzop

• What is the expected output? What do you see instead?
  To work!

• Please provide any additional information below.

It seems browser rendering is get broken if you resize the browser window while a page is loading and you have the settings below. Commenting this line

     settings.CefCommandLineArgs.Add("disable-gpu-vsync", "1"); //Disable Vsync

fixes the problem. I guess this will be only reproducible on machines with GPU.

• Does this problem also occur in the CEF Sample Application from http://opensource.spotify.com/cefbuilds/index.html?

Yes, if you enable these options and resize the window

        settings.CefCommandLineArgs.Add("disable-gpu", "1");
        settings.CefCommandLineArgs.Add("disable-gpu-compositing", "1");
        settings.CefCommandLineArgs.Add("disable-gpu-vsync", "1"); //Disable Vsync

[ekalchev]

Took me two days to figure out what is causing this. I hope someone to look at this sample app that is reproducing the issue. You need to start resizing the window while the page is loading.
https://ufile.io/jfzop

[amaitland]

Please no zip files as per the issue template.

Unclear if you tested with the CEF sample application, please clarify. If your experiencing the problem with cefclient there is no point opening an issue here.

[ekalchev]

This is reproducible with cefclient 3.3325.1758 but not with latest 3.3440.1805.gbe070f9. I guess it was fixed.

[amaitland]

You can try 67.0.0-pre01 which is based on 3.3396.1786.gd3e36d0 / Chromium 67.0.3396.79 if you haven't already tried a 3396 branched version.

master is currently based on 3.3440.1803 you can use a CI build if your game, seehttps://github.com/cefsharp/CefSharp#releases-1

Closing as upstream.

[wuruile]

This problem still exists on 69.0.0, so, this problem wasn't fixed at all !

[xzycn]

@wuruile Maybe you could try to use v71.0.0-pre01 now, otherwise v71.0.0 in a couple of days.It solves my problem :)

[TGolias-zz]

@xzycn @wuruile I can confirm the problem still exists on v71.0.0. That's actually one of the big reasons I may have to use WinForms version hosted in a WindowsFormsHost for the project I'm working on.

Weirdly I noticed that minimizing the Window hosting the WPF WebBrowser then maximizing it causes the browser to start redrawing again. If this gives anyone any ideas on a workaround let me know, I'd be willing to give them a shot.

-and if I end up finding anything I'll be sure to post my findings here.

[amaitland]

There is another bug in CEF causing problems on resize, you can track the progress at https://bitbucket.org/chromiumembedded/cef/issues/2614/osr-resizing-issue-surface-invariants

[CaptBli]

Similar to @TGolias, we have a couple of browsers that we use for two different sets of data. When it stops rendering we have to switch to the other browser and back and it starts rendering again.