Issue: 

Since upgrading my category or product page shows this error: Fatal error: Uncaught Error: Call to undefined method WC_Product_Variable::get_gallery_image_ids()

Solution:

Please make sure both the theme and WooCommerce are updated to their latest version. The latest version of Growrich is always compatible with the latest version of WooCommerce. If the problem persist make sure it's not a plugin that's causing it. Something that may not be yet compatible with your current version of WooCommerce. You can test that by deactivating all 3rd party plugins then run another test.