@WeirdAlex03 .local is reserved specifically for mDNS resolution. (RFC 6762.) Using it for other purposes can lead to unexpected behavior when software treats it as being used for what it's actually intended for.

.internal is not quite official yet; people are jumping the gun a bit. ICANN has resolved to never delegate it, but what will hopefully eventually become a RFC describing its intended use is still just an early Internet-Draft.

Shameless self-plug: michael.kjorling.se/blog/2024/

@arichtman