diff --git a/Extension/src/LanguageServer/client.ts b/Extension/src/LanguageServer/client.ts
index b0bd3ea76..7345b0c78 100644
--- a/Extension/src/LanguageServer/client.ts
+++ b/Extension/src/LanguageServer/client.ts
@@ -2655,7 +2655,7 @@ export class DefaultClient implements Client {
             });
 
             // TODO: Handle new associations without a reload.
-            this.associations_for_did_change = new Set<string>(["cu", "cuh", "c", "i", "cpp", "cc", "cxx", "c++", "cp", "hpp", "hh", "hxx", "h++", "hp", "h", "ii", "ino", "inl", "ipp", "tcc", "idl"]);
+            this.associations_for_did_change = new Set<string>(["cu", "cuh", "c", "i", "cpp", "cc", "cxx", "c++", "cp", "hpp", "hh", "hxx", "h++", "hp", "h", "ii", "ino", "inl", "ipp", "tcc", "txx", "tpp", "idl"]);
             const assocs: any = new OtherSettings().filesAssociations;
             for (const assoc in assocs) {
                 const dotIndex: number = assoc.lastIndexOf('.');
diff --git a/Extension/src/common.ts b/Extension/src/common.ts
index 4ce922d28..44b492678 100644
--- a/Extension/src/common.ts
+++ b/Extension/src/common.ts
@@ -165,7 +165,7 @@ export function getVcpkgRoot(): string {
 export function isHeaderFile(uri: vscode.Uri): boolean {
     const fileExt: string = path.extname(uri.fsPath);
     const fileExtLower: string = fileExt.toLowerCase();
-    return !fileExt || [".cuh", ".hpp", ".hh", ".hxx", ".h++", ".hp", ".h", ".inl", ".ipp", ".tcc", ".tlh", ".tli", ""].some(ext => fileExtLower === ext);
+    return !fileExt || [".cuh", ".hpp", ".hh", ".hxx", ".h++", ".hp", ".h", ".inl", ".ipp", ".tcc", ".txx", ".tpp", ".tlh", ".tli", ""].some(ext => fileExtLower === ext);
 }
 
 export function isCppFile(uri: vscode.Uri): boolean {