I also added .editorconfig to the C# project and the above content also appeared in the csproj file. The following two pieces of code are explained:
Editor Config Files Remove:
According to How to avoid conflicts in .csproj files. When you want to delete .editorconfig , the file can be removed from the project using the "delete" attribute. When you add .editorconfig, VS will not add .editorconfig in .csproj file if .editorconfig exists.
None Include:
According to In a .csproj file, what is for?. Because .editorconfig is not included in the project output group, nor compiled during build.
Second update:
Regarding being assigned to the same Itemgroup, the added activities must meet a certain standard or condition. At least the module keywords used to define them need to be the same (of course there are other standards here), but let’s look at the "EditorConfigFiles Remove" and "None Include" here, which are already different keyword definitions, so this the situation is normal