When you declare a plugin as "Editor" type, the plugin is still included in a packaged development build.
Found in 4.10.3 binary. Reproduced in 4.11 Preview 5, and Main CL 2870013
1. Open the editor
2. Go to Edit->Plugins
3. In the bottom right, click the new plugin option
4. Create a new blank Plugin "TestPlugin"
5. Restart the Editor
6. Open Visual Studio
7. In your project folder in Visual Studio, go into the Plugins folder and open TestPlugin.uplugin
8. In the .uplugin, next to "type", remove Developer and add Editor.
9. Build the project in VS
10. Navigate to your project folder->Engine->Plugins and copy the TestPlugin folder
11. Navigate to your engine installation directory->Plugins and paste the TestPlugin folder
12. Create a new project (or open an existing project) and go to Edit->Plugins->Other and enable TestPlugin
13. Restart the editor
14. Go to File->Package Project->Packaging Settings and uncheck the Use Pak File option.
15. Package the project for Win64 Development
16. When it completes, open the WindowsNoEditor folder and navigate to Engine->Plugins.
Result: The Test Plugin folder appears
Expected: As TestPlugin was labeled as Editor, it would not be included in a packaged build of the game.
Head over to the existing Questions & Answers thread and let us know what's up.