[#52: Mount location is not set error on new install] [#49: Download progress is not visible if dependencies are missing] [#51: javascript error] [#53: Busy notification is still visible when 'Install' button is available]

src/helpers.js

@@ -188,7 +188,7 @@ const _execProcessGetOutput = (cmd, working, args) => {
     }
     const proc = spawn(cmd, args, processOptions);
 
-    let output;
+    let output = '';
     proc.stdout.on('data', data => { output += data.toString(); });
 
     proc.on('error', (err) => { reject(err); });