Recently, I started looking up for details about implementing a blind signature on ed25519 cryptographic. I saw this article https://stan.bar/blindsig/ by Stanislaw Baranski about it. In the first point, it says that Bob generates random number (nonce) $k$ in range $(1, q-1)$, computes $r=k \times G (\mod p)$ $r=k×G(\mod p)$ and sends $r$ to Alice.
Now, how safe it is to make $r$ public and to share the same r across different signer? or should I make differents $r$ for each signer and still publicly publish all $r$?