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While it's not generally needed, you may want to step into ABP's source code while you are debugging your project.
All official ASP.NET Boilerplate NuGet packages are Sourcelink enabled. That means you can easily debug Abp.* NuGet packages within your project. To enable it, change Visual Studio (2017+) Debugging options as follows:
Once you enable it, you can step into (F11) the ASP.NET Boilerplate source code.