Safari on Mac, payment window won't load

I'm having issues on my Mac with Safari, running Sonoma. When I try and pay for a purchase via a card, the bank approval pop-up window is just white and hangs, anyone else getting this?

I've had to go over to using Firefox when buying on-line.

Sonoma is the latest version of MacOS (MacOS 14) and the latest build is 14.5

However, there may be some recent changes to Safari security/privacy defaults that need to be disabled for trusted sites to work (or was the case in my experience).

Make sure that you and whitelist your trusted site:

• Go to Safari > Settings for [Trusted Site]
• Uncheck [Enable content blockers]

See if that works.

Do you have any non-Apple security / ad-blocking products or Safari extensions on the Mac (Norton, McAfee, Kaspersky, etc.) that could be blocking specific elements? If so, try disabling them temporarily to see if it helps.

I'm fully up-to-date. I've not got any ad-blocking enabled, no content blockers. No 3rd party security, no extensions.

It's just the final banking pop-up window that asks to confirm the purchase on my phone banking app, just shows a white box and 'redirecting' but just hangs. I have now allowed pop-ups for the two sites I was having issues with, will see if that helps next time I order something.

Strange one.