Hi,
Sure, it had been already fixed for the upcoming release. If you need that now, you can apply the fix below.
1. Open up the wp-content/plugins/ajax-search-pro/backend/settings/assets/style.css file on your server
2. Replace it’s contents with this: https://gist.github.com/anag0/7a64edc7a51c76c9e4d7edfabba40cab
Before doing any changes, I strongly recommend having a full site back-up.