diff --git a/src/bg/user-script-install.js b/src/bg/user-script-install.js
index fbc9bea78..b8c8a81ef 100755
--- a/src/bg/user-script-install.js
+++ b/src/bg/user-script-install.js
@@ -2,7 +2,7 @@
 (function() {
 
 /// Receive a UserScriptInstall message.
-window.onUserScriptInstall = async function(message, sender) {
+window.onUserScriptInstall = function(message, sender) {
   if (message.details) {
     let downloader = new Downloader(message.details, sender);
     downloader.start(function() {
@@ -11,7 +11,20 @@ window.onUserScriptInstall = async function(message, sender) {
       }
     });
   } else if (message.source) {
-    return await UserScriptRegistry.installFromSource(message.source);
+    // Returning a promise
+    return UserScriptRegistry.installFromSource(message.source)
+        .catch(err => {
+          if (err instanceof ParseError) {
+            console.warn(err);
+            chrome.notifications.create({
+              'type': 'basic',
+              'title': 'Failed to import script',
+              'message': err.message,
+            });
+          }
+          // Propagate to the message listener
+          throw err;
+        });
   }
 }
 
diff --git a/src/bg/user-script-registry.js b/src/bg/user-script-registry.js
index 49ae8b9dc..611f3d118 100644
--- a/src/bg/user-script-registry.js
+++ b/src/bg/user-script-registry.js
@@ -89,7 +89,12 @@ async function installFromSource(source) {
           console.error('Error looking up script!', event);
         };
       } catch (e) {
-        console.error('at installFromSource(), db fail:', e);
+        if (e instanceof ParseError) {
+          // Noop, will be handled by caller
+        } else {
+          console.error('at installFromSource(), db fail:', e);
+        }
+        reject(e);
       }
     });
   });
diff --git a/src/content/import/import-script.js b/src/content/import/import-script.js
index 426331939..0fa612c34 100644
--- a/src/content/import/import-script.js
+++ b/src/content/import/import-script.js
@@ -14,7 +14,12 @@ function onImportUserScript(event) {
       // Done loading
       chrome.runtime.sendMessage(
           {'name': 'UserScriptInstall', 'source': fr.result},
-          uuid => openUserScriptEditor(uuid));
+          uuid => {
+            // TODO: When switching to promises use `.catch`
+            if (!chrome.runtime.lastError) {
+              openUserScriptEditor(uuid);
+            }
+          });
     }
   };
   fr.readAsText(importScript.files[0]);