diff --git a/packages/app-js/src/index.tsx b/packages/app-js/src/index.tsx
index d827e85246..f425bff289 100644
--- a/packages/app-js/src/index.tsx
+++ b/packages/app-js/src/index.tsx
@@ -108,7 +108,7 @@ class App extends React.PureComponent<Props, State> {
     );
   }
 
-  private runJs = (): void => {
+  private runJs = async (): Promise<void> => {
     const { api } = this.props;
     const { code } = this.state;
     const { keyring } = uiKeyring;
@@ -129,6 +129,8 @@ class App extends React.PureComponent<Props, State> {
       window: null
     };
 
+    await this.injected.api.isReady;
+
     // squash into a single line so exceptions (with linenumbers) maps to the same line/origin
     // as we have in the editor view (TODO: Make the console.error here actually return the full stack)
     const exec = `(async ({${Object.keys(this.injected).join(',')}}) => { try { ${code} } catch (error) { console.error(error); } })(injected);`;