src/vs/workbench/contrib/notebook/browser/notebookServiceImpl.ts/NotebookProviderInfoStore/getContributedNotebook
class NotebookProviderInfoStore:	getContributedNotebook(resource: URI): readonly NotebookProviderInfo[] {
		const result: NotebookProviderInfo[] = [];
		for (const info of this._contributedEditors.values()) {
			if (info.matches(resource)) {
				result.push(info);
			}
		}
		if (result.length === 0 && resource.scheme === Schemas.untitled) {
			// untitled resource and no path-specific match => all providers apply
			return Array.from(this._contributedEditors.values());
		}
		return result;
	}