Hey Primi2k ,
Thanks for your reply! Hope you've had a great weekend!
I've just deployed a WordPress 6.2.2 environment (with PHP 8.2) and did some tests. Unfortunately I wasn't able to replicate the isuse.
When trying to onboard your site and check the network-tab (from the developer tools), does it succesfully send the
nonce as a parameter in the URL (in this case, it's for the URL
/wp-json/buttonizer/connect?nonce=)? Or does it not contain any value?
If you're able to, we can take a look on your site ourselves to investigate further, but then we'll make it a private ticket first 🙂
Let me know!