Safari and Firefox CORS issues

[art1c0]

Safari on Mac Version 12.1.1 (14607.2.6.1.1)
Running burner without metamask - the balance is not shown.
Console shows many errors regarding failed requests to infura due to CORS issues.

[Error] Failed to load resource: Origin http://localhost:3000 is not allowed by Access-Control-Allow-Origin. (https://mainnet.infura.io/v3/f039330d8fb747e48a7ce98f51400d65)

Firefox 67.0.1 (64-bit) on Mac

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://rinkeby.infura.io/v3/f039330d8fb747e48a7ce98f51400d65. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing).

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://rinkeby.infura.io/v3/f039330d8fb747e48a7ce98f51400d65. (Reason: CORS request did not succeed).