Trouble loading maps in a website in Safari

mOS Tahoe running on both Mac and MacBook Air.

iOS 26 running on iPhone and iPad.

I use a website to plan trips. I load a map you can plot points on. Since the upgrades, the map will not load in Safari on Mac and MacBook, BUT will load in Safari on iPhone and iPad.

The site will load in Google, Firefox, and Opera with no trouble.

I have contacted the site's developer, but there has been no response yet.

Is this a Tahoe? Safari problem, or has my Safari got settings that are stopping maps from loading? I am just a normal person, not a web developer, so go easy with the techy stuff with me

This is the website. https://suewright.travelmap.net/bordeaux-2026 - TIA