Nobody has given a definitive answer because it’s still unclear why it isn’t working. Ordinarily, the security system blocks non-browser requests, but as Admin mentioned this request is coming from your browser, so it would be unusual for the security system to not allow it, unless it travels to another server first like GR9 suggested. I’m not seeing anything helpful from the screenshot you sent. There don’t look to be any requests to another server beside’s Google’s fonts, though that doesn’t guarantee that there aren’t any non-browser requests happening in the backend, especially since Spectra’s support thinks it could be a block on InfinityFree’s side.
Spectra knows more about their software and how it works than anyone here would. A more productive path forward may be to refer their support to this article and ask them if that could be causing the problem.