src/vs/workbench/contrib/files/browser/editors/fileEditorHandler.ts/FileEditorWorkingCopyEditorHandler/installHandler
class FileEditorWorkingCopyEditorHandler:	private installHandler(): void {
		this._register(this.workingCopyEditorService.registerHandler({
			handles: workingCopy => workingCopy.typeId === NO_TYPE_ID && this.fileService.hasProvider(workingCopy.resource),
			// Naturally it would make sense here to check for `instanceof FileEditorInput`
			// but because some custom editors also leverage text file based working copies
			// we need to do a weaker check by only comparing for the resource
			isOpen: (workingCopy, editor) => isEqual(workingCopy.resource, editor.resource),
			createEditor: workingCopy => this.textEditorService.createTextEditor({ resource: workingCopy.resource, forceFile: true })
		}));
	}