When inspecting in Firefox after a full and working setup of serverside GA4 and GTM according your guides I test it with Ublock on in Firefox and I get the following erros in the Network panel:
Some cookies are missing the recommended “SameSite“ attribute(the listed cookies are all ga cookies)
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at followed by an endpoint with my custom gtm.domain subdomain and folder /g/collect? and a lot of parameters.
I’m realy a newbee into this and I’m not realy sure where to look next.
Thanks for the reply Dan! So the issue is on https://www.5broden2vissencatering.nl/ in Firefox with the extention (addblocker) UBlock Origin ON. Without the add blocker I only get the: “Some cookies are misusing the recommended “SameSite“ attribute” error.
@Sjoerd I don’t think that’s CORS related as your original message suggests, it looks like UBlock is recognising the /collect pattern (GA4 hits) and blocks based on that, when I try to send the same hit with a different pattern - everything goes through.
No remedy for this presently (this GA4 specifically, you can see that gtm is still loaded) although we may yet come up with something