diff --git a/devtools/server/tests/browser/head.js b/devtools/server/tests/browser/head.js
index 41a0def81750..e22be5f610b3 100644
--- a/devtools/server/tests/browser/head.js
+++ b/devtools/server/tests/browser/head.js
@@ -61,7 +61,9 @@ function initDebuggerServer() {
     // Sometimes debugger server does not get destroyed correctly by previous
     // tests.
     DebuggerServer.destroy();
-  } catch (ex) { }
+  } catch (e) {
+    info(`DebuggerServer destroy error: ${e}\n${e.stack}`);
+  }
   DebuggerServer.init();
   DebuggerServer.addBrowserActors();
 }