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Can you give me direct link to your page to check page source for errors

Virtually every page on the site has a map, which displayed a route before the migration to Joomla 4.
 
To find the origin of the error, I did a completely "clean" installation locally, with only Joomla 4.3.1 and ZhGoogleMap-j4-13.23.5.3-final. With this test site, we also do not see the route, nor the contour lines.
 
The pages show no errors.
 
Links to some pages:
  www.valroc.net/pointe-de-tardevant
  www.valroc.net/le-lac-blanc-depuis-nevache
  www.valroc.net/pierra-menta-bonhomme-trek-de-3-jours

At first I can see error
"Content Security Policy: The page’s settings blocked the loading of a resource at maps.googleapis.com/maps/api/ "

Check your site/server settings

I apologize but I don't understand.
 
For me the console only shows a warning but no error.
 
How do you display other anomalies please (I am not a professional)?
 
 
I still believe that there is a problem with the display of a KML with the "Path" tab of ZhGoogleMap (which has nothing to do with the site/server parameters) because we obtain a normal KML display with the "Map" tab.
 
Display that works with the "Map" tab: www.valroc.net/test

Hi
I click your link and can see map with KML layer

Yes, exactly it works because it is a display using the "Map" tab.
The disadvantage with this display is that there are no level curves.

With the "Path" tab, nothing appears, neither the route nor the level curve.

Pages not working:
www.valroc.net/pointe-de-tardevant
www.valroc.net/le-lac-blanc-depuis-nevache
www.valroc.net/pierra-menta-bonhomme-trek-de-3-jours