Gnosis recently migrated their URLs from https://gnosis-safe.io -> https://safe.global/, and the main app is now https://app.safe.global
When I was trying to access this through my home ASUS AC1900 router it wasn’t recognising either safe I was connected to, and refused to let me connect my wallet at all.
Looking at the network tab I could see the following errors
Code 902: Error loading Safe Apps list (Network request failed)
Code 600: Error fetching Safe info (Network request failed)
It turned out the the ASUS was treating the URL as a threat and not allowing the connection to work.
I was able to connect to my router using http://router.asus.com/
and navigated to the AiProtection section.
Select the Malcious Sites Blocking tab, and then select the edit button above the “Details of Successfully Protected Events”.
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Add the following URLs to the allow list
app.safe.global
safe.global
safe-client.safe.global
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Voila, you should be able to access your Safe again.