WinDbg

Download a binary with debug symbols

Download SDK installer from https://developer.microsoft.com/windows/downloads/windows-sdk/
Start winsdksetup.exe, select "Download the Windows Software Development Kit ...." and press "Next".
Uncheck all features except "Debugging Tools for Windows x64".
After the download is complete, enter the download directory and run "X64 Debuggers And Tools-x64_en-us.msi" from the Installers subdirectory.

Search for "WinDbg (X64)" on the start menu and run it.
Select "File"->"Open Executable" from the application menu and select the main executable file you unpacked before, e.g. <unpack-root>\bin\umbrello5.exe.
Select ""Debug"->"Go" to start the application. In case of a crash it will stop automatically.
Select "View"->"Processes and Threads" from the application menu and select the main thread (id 000) if not already selected.
Select "View"->"Callstack" to see the backtrace.
Press "Source" in the call stack windows to see the source information.
To save the call stack to the clipboard, press the icon on the left side of the Close button in the window title.
Open a new bugs at https://bugs.kde.org and paste the clipboard content into that bug.

Note: Normally KF5 applications use DrKonqi to automatically generate a backtrace after a crash

cdb is the command line version of WinDbg and could also be used to generate back traces. To use cdb follow these steps:

Download a binary with debug symbols
Download a debugger
start cdb (normally installed into C:\Program Files (x86)\Windows Kits\10\Debuggers\x64) with:
```
cdb -g -lines <executable>
```
After the application crashes, enter the following command to select the main thread, if not already selected
```
~0 s
```
Then show the backtrace with
```
k
```

You can save this backtrace to the clipboard and paste it into the related bug report.

To display debug messages, you must start this tool before the associated KDE application.