I have a Wordpress website focused on winter sports vacations in Iceland: link
Every plugin, WordPress core, and theme are up to date.
Using Woocommerce for my online store. However, activating the Woocommerce plugin causes the site to slow down significantly. Deactivating it speeds up the site again.
The theme I am using is supposedly compatible with Woocommerce according to the developer, but they are unable to identify the cause of the slowdown.
Tried optimizing speed and caching with WP-Rocket plugin, but no improvement was seen.
Analysis from Pingdom Tools and GTMetrix indicate a major delay in loading admin-ajax.php?action=grandtour_custom_css
You can view the test results here: link
Any advice on how to tackle this issue?