diff --git a/extensions/typescript-language-features/src/typescriptServiceClient.ts b/extensions/typescript-language-features/src/typescriptServiceClient.ts
index 01d98a87812..f029bf4cef0 100644
--- a/extensions/typescript-language-features/src/typescriptServiceClient.ts
+++ b/extensions/typescript-language-features/src/typescriptServiceClient.ts
@@ -743,6 +743,8 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 			case fileSchemes.file:
 			case fileSchemes.untitled:
 			case fileSchemes.vscodeNotebookCell:
+			case fileSchemes.memFs:
+			case fileSchemes.vscodeVfs:
 				for (const root of roots.sort((a, b) => a.uri.fsPath.length - b.uri.fsPath.length)) {
 					if (resource.fsPath.startsWith(root.uri.fsPath + path.sep)) {
 						return root.uri.fsPath;
diff --git a/extensions/typescript-language-features/src/utils/fileSchemes.ts b/extensions/typescript-language-features/src/utils/fileSchemes.ts
index 42067c3eae4..69c54ac62e4 100644
--- a/extensions/typescript-language-features/src/utils/fileSchemes.ts
+++ b/extensions/typescript-language-features/src/utils/fileSchemes.ts
@@ -10,6 +10,8 @@ export const git = 'git';
 export const vsls = 'vsls';
 export const walkThroughSnippet = 'walkThroughSnippet';
 export const vscodeNotebookCell = 'vscode-notebook-cell';
+export const memFs = 'memfs';
+export const vscodeVfs = 'vscode-vfs';
 
 export const semanticSupportedSchemes = [
 	file,