What is the router ID length supported by OSPFv3?

Comprehensive and Detailed In-Depth Explanation:

OSPFv3, which supports IPv6, uses a router ID that is 32 bits in length, similar to OSPFv2. The router ID in OSPF is always a 32-bit number, typically represented in an IPv4 address format (dotted decimal). Although OSPFv3 is designed to support IPv6, itstill relies on a 32-bit router ID for identification, which must be unique within an OSPF domain. The router ID does not change even though the protocol itself supports IPv6 addresses (128 bits).