diff --git a/extension/background.js b/extension/background.js
index da4e37b..10b99a0 100644
--- a/extension/background.js
+++ b/extension/background.js
@@ -275,7 +275,8 @@ router["/tabs/by-id/*/control"] = {
     // see https://developer.chrome.com/extensions/tabs
     await browser.tabs[command](tabId);
     return {size: stringToUtf8Array(buf).length};
-  }
+  },
+  async truncate({path, size}) { return {}; }
 };
 
 router["/tabs/by-title"] = {
diff --git a/test.c b/test.c
index 15e2c51..a5f928e 100755
--- a/test.c
+++ b/test.c
@@ -15,10 +15,11 @@ int file_contents_equal(char* path, char* contents) {
 }
 
 // integration tests
-int main() {
+int main(int argc, char** argv) {
     assert(system("echo about:blank > fs/mnt/tabs/create") == 0);
     assert(file_contents_equal("fs/mnt/tabs/last-focused/url", "about:blank"));
     assert(system("file fs/mnt/tabs/last-focused/screenshot.png") == 0);
-    
+    assert(system("echo remove > fs/mnt/tabs/last-focused/control") == 0);
+
     assert(1); printf("Done!\n"); 
 }