I am experiencing a problem never seen before.
The following url should display an image.
https://www.meteosvizzera.admin.ch/product/output/radar/precipitation/VRAG05.CCSK_20190820_2335.png
This works only the first time I visit it, then it gives me a 403 error independently to the browser I chosed. With wget command it gives me immediately the error 403.
This link resides within the "meteosvizzera" website (https://www.meteosvizzera.admin.ch/home.html?tab=alarm, click on "Precipitazioni" and then inspect the code over the map of switzerland and you will see the image url). Copy and paste this url on a new tab and you will see the error 403 after refreshing the browser.
I wonder the following thing. If an image is shown on the website, how can it be blocked with a direct access pointing the image? What configuration was set to avoid such a mechanism?
Is there a possibility for me to be able to point the image even by refreshing the browser after the first attempt?
The following header made it work for me:
wget --header="Referer: https://www.meteosvizzera.admin.ch/home.html?tab=rain" https://www.meteosvizzera.admin.ch/product/output/inca/precipitation-forecast/version__20190827_0023/Rain_20190827_0030.png