[Qtwebengine] Debugging issue with QWebEngineView freezing on Qt 5.12.3

[Allan Jensen]

On Freitag, 5. Juli 2019 07:00:32 CEST Thuan Seah Tan wrote:
> Hi all,
> 
> We are currently migrating our software from Qt 5.4.1 to Qt 5.12.3 and
> encountered an issue where the QWebEngineView would freeze (i.e. not
> responding to mouse click on links but still responding to window resize)
> but the main application thread runs fine.
> 
> Currently we suspect it has something to do with how we handle drag and
> drop. I am trying to debug this in Visual Studio 2017 and there are a
> number of Chrome threads which I can't inspect the callstack for. They all
> seem to be external code for some reason. Beyond that I don't see any
> thread that could be related to QWebEngineView. Can anyone provide some
> assistance as to how to troubleshoot the freezing issue?

To get full debug info edit src/core/config/common.pri, there are two GN args 
that remove debug-info from blink and v8, comment those out. Note this will 
the debug library much larger (up to 4GB).

As for the thread with QWebEngineView, it is the main UI-thread, thread 1.

'Allan