diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1356175..4a3f72d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 # [0.0.19]
 
+* Added activation support for C language.
 * Added setting `iwyu.fix.fix_header` which fixes includes in the corresponding header for a given implementation file (e.g. foo.h when fixing foo.cpp).
 
 # [0.0.18]
diff --git a/package.json b/package.json
index 3ec8cfb..c1f4082 100644
--- a/package.json
+++ b/package.json
@@ -7,7 +7,7 @@
     "Include What You Use",
     "include-what-you-use"
   ],
-  "version": "0.0.18",
+  "version": "0.0.19",
   "publisher": "helly25",
   "license": "Apache-2.0",
   "repository": {
@@ -16,13 +16,14 @@
   },
   "icon": "images/logo.png",
   "engines": {
-    "vscode": "^1.78.0"
+    "vscode": "^1.92.0"
   },
   "categories": [
     "Other"
   ],
   "activationEvents": [
-    "onLanguage:cpp"
+    "onLanguage:cpp",
+    "onLanguage:c"
   ],
   "main": "./out/extension.js",
   "contributes": {
diff --git a/src/extension.ts b/src/extension.ts
index fb1abfa..098e9b2 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -41,6 +41,8 @@ export const ERROR = vscode.LogLevel.Error;
 
 const logger: vscode.LogOutputChannel = vscode.window.createOutputChannel("IWYU", { log: true });
 
+const supportedLanguages = ["cpp", "c"];
+
 function log(severity: vscode.LogLevel, message: string, ...args: any[]) {
     switch (severity) {
         case vscode.LogLevel.Off: return;
@@ -395,11 +397,13 @@ class Extension {
 
         this.subscribeToDocumentChanges(context, iwyuDiagnostics);
 
-        context.subscriptions.push(
-            vscode.languages.registerCodeActionsProvider('cpp', new IwyuQuickFix(this.configData), {
-                providedCodeActionKinds: IwyuQuickFix.providedCodeActionKinds
-            })
-        );
+        for (const lang of supportedLanguages) {
+            context.subscriptions.push(
+                vscode.languages.registerCodeActionsProvider(lang, new IwyuQuickFix(this.configData), {
+                    providedCodeActionKinds: IwyuQuickFix.providedCodeActionKinds,
+                })
+            );
+        }
 
         context.subscriptions.push(vscode.commands.registerCommand(IWYU_COMMAND_ONE, () => { this.iwyuCommandOne(); }));
         context.subscriptions.push(vscode.commands.registerCommand(IWYU_COMMAND_ALL, () => { this.iwyuCommandAll(); }));
@@ -762,9 +766,17 @@ class Extension {
     }
 
     private iwyuDiagnosticsRefresh(doc: vscode.TextDocument, iwyuDiagnostics: vscode.DiagnosticCollection) {
-        if (doc.languageId !== "cpp") {
+        // Only process real files (not logs, etc.)
+        if (doc.uri.scheme !== "file") {
             return;
         }
+
+        // Only process supported languages
+        if (!supportedLanguages.includes(doc.languageId)) {
+            log(DEBUG, `Unsupported language: ${doc.languageId}. Skipping.`);
+            return;
+        }
+
         this.configData.updateConfig();
         let diagnosticsOnlyRe: string = this.configData.config.get("diagnostics.only_re", "");
         if (typeof diagnosticsOnlyRe  !== "string" || String(diagnosticsOnlyRe) === "true") {