diff --git a/index.js b/index.js
index da80968..28fbb22 100644
--- a/index.js
+++ b/index.js
@@ -103,6 +103,8 @@ const ContainerService = {
           sendReply(this[message.method](message));
         }
       });
+    }).catch(() => {
+      throw new Error("WebExtension startup failed. Unable to continue.");
     });
   },
 
@@ -194,8 +196,7 @@ const ContainerService = {
 
   showTabs(args) {
     if (!("userContextId" in args)) {
-      Promise.reject("showTabs must be called with userContextId argument.");
-      return;
+      return Promise.reject("showTabs must be called with userContextId argument.");
     }
 
     const promises = [];
@@ -279,6 +280,8 @@ const ContainerService = {
 
       Promise.all(promises).then(() => {
         resolve(list);
+      }).catch((e) => {
+        reject(e);
       });
     });
   },
@@ -386,8 +389,7 @@ const ContainerService = {
 
   getIdentity(args) {
     if (!("userContextId" in args)) {
-      Promise.reject("getIdentity must be called with userContextId argument.");
-      return;
+      return Promise.reject("getIdentity must be called with userContextId argument.");
     }
 
     const identity = ContextualIdentityService.getIdentityFromId(args.userContextId);
@@ -397,8 +399,7 @@ const ContainerService = {
   createIdentity(args) {
     for (let arg of [ "name", "color", "icon"]) { // eslint-disable-line prefer-const
       if (!(arg in args)) {
-        Promise.reject("createIdentity must be called with " + arg + " argument.");
-        return;
+        return Promise.reject("createIdentity must be called with " + arg + " argument.");
       }
     }
 
@@ -415,8 +416,7 @@ const ContainerService = {
 
   updateIdentity(args) {
     if (!("userContextId" in args)) {
-      Promise.reject("updateIdentity must be called with userContextId argument.");
-      return;
+      return Promise.reject("updateIdentity must be called with userContextId argument.");
     }
 
     const identity = ContextualIdentityService.getIdentityFromId(args.userContextId);
@@ -436,8 +436,7 @@ const ContainerService = {
 
   removeIdentity(args) {
     if (!("userContextId" in args)) {
-      Promise.reject("removeIdentity must be called with userContextId argument.");
-      return;
+      return Promise.reject("removeIdentity must be called with userContextId argument.");
     }
     return Promise.resolve(ContextualIdentityService.remove(args.userContextId));
   },
diff --git a/package.json b/package.json
index c8dcdf6..89bfcc3 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
   "title": "Containers Experiment",
   "description": "Containers works by isolating cookie jars using separate origin-attributes defined visually by colored ‘Container Tabs’. This add-on is a modified version of the containers feature for Firefox Test Pilot.",
   "version": "0.0.1",
-  "author": "Luke Crouch & Jonathan Kingston",
+  "author": "Andrea Marchesini, Luke Crouch and Jonathan Kingston",
   "bugs": {
     "url": "https://github.com/mozilla/testpilot-containers/issues"
   },
diff --git a/webextension/js/popup.js b/webextension/js/popup.js
index 1241cc4..b2ef64e 100644
--- a/webextension/js/popup.js
+++ b/webextension/js/popup.js
@@ -44,6 +44,10 @@ const Logic = {
       } else {
         this.showPanel(P_ONBOARDING_1);
       }
+    })
+
+    .catch(() => {
+      throw new Error("Failed to retrieve the identities. We cannot continue.");
     });
   },
 
@@ -73,6 +77,9 @@ const Logic = {
         panelElement.classList.add("hide");
       }
       document.querySelector(this._panels[panel].panelSelector).classList.remove("hide");
+    })
+    .catch(() => {
+      throw new Error("Failed to show panel " + panel);
     });
   },
 
@@ -186,6 +193,8 @@ Logic.registerPanel(P_CONTAINERS_LIST, {
         method: "sortTabs"
       }).then(() => {
         window.close();
+      }).catch(() => {
+        window.close();
       });
     });
   },
@@ -221,6 +230,8 @@ Logic.registerPanel(P_CONTAINERS_LIST, {
             });
           }).then(() => {
             window.close();
+          }).catch(() => {
+            window.close();
           });
         } else if (e.target.matches(".info")) {
           Logic.showPanel(P_CONTAINER_INFO, identity);
@@ -256,6 +267,8 @@ Logic.registerPanel(P_CONTAINER_INFO, {
         userContextId: identity.userContextId
       }).then(() => {
         window.close();
+      }).catch(() => {
+        window.close();
       });
     });
 
@@ -318,6 +331,8 @@ Logic.registerPanel(P_CONTAINER_INFO, {
             tabId: tab.id,
           }).then(() => {
             window.close();
+          }).catch(() => {
+            window.close();
           });
         });
       }
@@ -418,6 +433,8 @@ Logic.registerPanel(P_CONTAINER_EDIT, {
         return Logic.refreshIdentities();
       }).then(() => {
         Logic.showPreviousPanel();
+      }).catch(() => {
+        Logic.showPanel(P_CONTAINERS_LIST);
       });
     });
   },
@@ -453,6 +470,8 @@ Logic.registerPanel(P_CONTAINER_DELETE, {
         return Logic.refreshIdentities();
       }).then(() => {
         Logic.showPreviousPanel();
+      }).catch(() => {
+        Logic.showPanel(P_CONTAINERS_LIST);
       });
     });
   },