Adding a Module to Plugin crashes Unreal Engine: "Assertion failed: IsValid() UE_4.26\...\Templates/SharedPointer.h [Line: 890]"


I’m trying to add a new module to a plugin I’m making. Basically I already wrote a runtime plugin and now I want to add an editor module so I can make a nice little UI to go with it. What I did was create a new blank UE4 project, then add a new plugin with the “Editor Standalone Window” preset, then copied the new plugin files to the plugin folder in my initial project.

The structure of my plugin folder now looks like this:

 ⤷ MyPlugin
      ⤷ Source
          ⤷ MyPlugin (runtime)
	          ⤷ Private
              ⤷ Public
          ⤷ MyPluginEditor (editor)
	          ⤷ Private
	          ⤷ Public

Then I edited the .uplugin file to add the new module to the “Modules” list. The project compiles fine in visual studio, and looking at the logs I don’t think there’s any issue with compiling. However when I launch the UE4 project, it just crashes with the following message :

Assertion failed: IsValid() [File:C:\Program Files\Epic Games\UE_4.26\Engine\Source\Runtime\Core\Public\Templates/SharedPointer.h] [Line: 890]

It launches correctly when I remove the module from the .uproject file, so the problem has to be with the new module. But as I mentionned the code comes straight from the “Editor Standalone Window” preset. So all i can think of is there’s something I need to change in the editor module’s Build.cs file. I just don’t know what. Any help?