Slow on first load + warnings

Hi,

When using the Hestia theme, the initial load of the site gets extremely slow (>40 secs) or is not loaded at all. After 2nd or third load all the pages work fine. If not used for some time (like over an hour): same problem again.

Also get messages like below (on Console of Chrome DevTools):

• jquery.min.js?ver=3.7.0:2 [Violation] Listener added for a synchronous ‘DOMNodeInserted’ DOM Mutation Event. This event type is deprecated (https://w3c.github.io/uievents/#legacy-event-types) and work is underway to remove it from this browser. Usage of this event listener will cause performance issues today, and represents a risk of future incompatibility. Consider using MutationObserver instead.
• [Intervention] Slow network is detected. See https://www.chromestatus.com/feature/5636954674692096 for more details. Fallback font will be used while loading: https://noisme.nl/wp-content/themes/hestia/assets/font-awesome/webfonts/fa-brands-400.woff2
• Failed to load resource: net::ERR_NETWORK_CHANGED

If standard WP theme (like twenty twenty-three) is activated, these messages do not occur, neither any delay in functionality. Regarding server speed or so: other sites on same server have correct functionality without issues.

Are these messages maybe related to this problem? How to solve?
Theme is looking nice but not with this performance and warnings.

Thanks for your support in advance.

Regards,
Etienne

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