Firefox blocking request on Data Sources/Gateways settings page due to CORS Error

[Anonymous]

I cannot load my on-prem gateways in Firefox but can in Chrome. I found that two requests, an OPTIONS request and a GET request, both to arc.msn.com domain, are being blocked by Firefox. The OPTIONS request is status 400 Bad Request, CORS Missing Allow Origin, the GET request has no status and says NS_ERROR_DOM_BAD_URI, leading me to believe the OPTIONS request is affecting the GET. In Chrome both are status 200. I have no plugins in Chrome (I prefer not to use software that so obviously tracks me) and I have disabled my array of ad and tracking blockers in Firefox. See the below screen shots.

Firefox

Firefox

Chrome

Chrome

[v-cazheng-msft]

Hi @Anonymous 

If you see a   red circle with a diagonal slash, it means the response is blocked by the browser or server. Normally, Power BI won’t block the requests from users. As the description, requests will be handled when using Chrome but not Firefox, which proves that Power BI can properly receive the requests from you and return response.

Please check the block list of your Firefox browser and unblock the requests if you does configure like this. Also, NS_ERROR_DOM_BAD_URI error refers to Access to restricted URI denied, you may cause by the same-origin-policy issue. This means that either the port, domain, or protocol is not the same between the URI that you are sending a request TO and the URL that you are sending the request FROM. So, you could try to clear the cookie and the cache in your FireFox browser as well.

Attach some links that may help you.

OPTIONS - HTTP | MDN (mozilla.org)

Network request list — Firefox Source Docs documentation (mozilla.org)

Best Regards,

Community Support Team _ Caiyun

[v-cazheng-msft]

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