src/vs/workbench/contrib/mergeEditor/browser/mergeEditorInput.ts/MergeEditorInput/capabilities
class MergeEditorInput:	override get capabilities(): EditorInputCapabilities {
		let capabilities = super.capabilities | EditorInputCapabilities.MultipleEditors;
		if (this.useWorkingCopy) {
			capabilities |= EditorInputCapabilities.Untitled;
		}
		return capabilities;
	}