diff --git a/browser/devtools/webide/content/webide.js b/browser/devtools/webide/content/webide.js
index aec5481c8fd..61e12a4645e 100644
--- a/browser/devtools/webide/content/webide.js
+++ b/browser/devtools/webide/content/webide.js
@@ -246,8 +246,11 @@ let UI = {
       this.unbusy();
     }, (e) => {
       this.cancelBusyTimeout();
-      UI.reportError("error_operationFail", operationDescription);
-      console.error(e);
+      let operationCanceled = e && e.canceled;
+      if (!operationCanceled) {
+        UI.reportError("error_operationFail", operationDescription);
+        console.error(e);
+      }
       this.unbusy();
     });
     return promise;
diff --git a/browser/devtools/webide/modules/app-manager.js b/browser/devtools/webide/modules/app-manager.js
index 3263e67551d..d5460101e29 100644
--- a/browser/devtools/webide/modules/app-manager.js
+++ b/browser/devtools/webide/modules/app-manager.js
@@ -337,7 +337,7 @@ exports.AppManager = AppManager = {
       try {
         this.selectedRuntime.connect(this.connection).then(
           () => {},
-          () => {deferred.reject()});
+          deferred.reject.bind(deferred));
       } catch(e) {
         console.error(e);
         deferred.reject();
diff --git a/browser/devtools/webide/modules/runtimes.js b/browser/devtools/webide/modules/runtimes.js
index db312c35f52..daa3d946851 100644
--- a/browser/devtools/webide/modules/runtimes.js
+++ b/browser/devtools/webide/modules/runtimes.js
@@ -126,11 +126,13 @@ let gRemoteRuntime = {
       return promise.reject();
     }
     let ret = {value: connection.host + ":" + connection.port};
-    Services.prompt.prompt(win,
-                           Strings.GetStringFromName("remote_runtime_promptTitle"),
-                           Strings.GetStringFromName("remote_runtime_promptMessage"),
-                           ret, null, {});
+    let title = Strings.GetStringFromName("remote_runtime_promptTitle");
+    let message = Strings.GetStringFromName("remote_runtime_promptMessage");
+    let ok = Services.prompt.prompt(win, title, message, ret, null, {});
     let [host,port] = ret.value.split(":");
+    if (!ok) {
+      return promise.reject({canceled: true});
+    }
     if (!host || !port) {
       return promise.reject();
     }