extensions/markdown-language-features/src/languageFeatures/workspaceSymbolProvider.ts/MdWorkspaceSymbolProvider/provideWorkspaceSymbols
class MdWorkspaceSymbolProvider:	public async provideWorkspaceSymbols(query: string): Promise<vscode.SymbolInformation[]> {
		const allSymbols = (await this._cache.getAll()).flat();
		return allSymbols.filter(symbolInformation => symbolInformation.name.toLowerCase().indexOf(query.toLowerCase()) !== -1);
	}