src/vs/workbench/services/untitled/common/untitledTextEditorModel.ts/UntitledTextEditorModel/name
class UntitledTextEditorModel:	get name(): string {
		// Take name from first line if present and only if
		// we have no associated file path. In that case we
		// prefer the file name as title.
		if (this.configuredLabelFormat === 'content' && !this.hasAssociatedFilePath && this.cachedModelFirstLineWords) {
			return this.cachedModelFirstLineWords;
		}

		// Otherwise fallback to resource
		return this.labelService.getUriBasenameLabel(this.resource);
	}