Original text:
3. <del> Names are formed using Port-Prefix Naming (SVCB Section 2.3), with a scheme of "dns".  For example, SVCB records for a DNS service identified as "dns1.example.com" would be located at "_dns.dns1.example.com". </del>  3.1. When a non-default port number is part of a service identifier, Port- Prefix Naming places the port number in an additional a prefix on the name.  For example, SVCB records for a DNS service identified as <del> "dns1.example.com:9953" would be located at "_9953._dns.dns1.example.com".  If two DNS services operating on </del>  different port numbers provide different behaviors, this arrangement allows them to preserve the distinction when specifying alternative endpoints. 4.1. <del> This key indicates the set of supported protocols (SVCB Section 6.1). There is no default protocol, so the "no-default-alpn" key does not apply, and the "alpn" key MUST be present. </del>  If the protocol set contains any HTTP versions (e.g. "h2", "h3"), then the record indicates support for DNS over HTTPS DOH, and the 4.2. <del> This key is used to indicate the target port for connection ((SVCB Section 6.2)).  If omitted, the client SHALL use the default port for each transport protocol (853 for DNS over TLS DOT, 443 for DNS over HTTPS). </del>  This key is automatically mandatory if present.  (See Section 7 of SVCB for the definition of "automatically mandatory".)

Reviewer comments:
The lack of quoting in some of the examples might make it harder to see what constitutes example and what is punctuation. Highlighting and fonts in the HTML rendering are subtle and not present in text renderings (any more). I've also changed some section references. I'm happy to split that off into a different change or use the form if you prefer that.

Revised text:
3.  <ins> Names are formed using Port-Prefix Naming (Section 2.3 of SVCB), with a scheme of "dns".  For example, SVCB records for a DNS service identified as ""dns1.example.com"" would be located at ""_dns.dns1.example.com"". </ins> 3.1. When a non-default port number is part of a service identifier, Port- Prefix Naming places the port number in an additional a prefix on the name.  For example, SVCB records for a DNS service identified as  <ins> ""dns1.example.com:9953"" would be located at ""_9953._dns.dns1.example.com"".  If two DNS services operating on </ins> different port numbers provide different behaviors, this arrangement allows them to preserve the distinction when specifying alternative endpoints. 4.1.  <ins> This key indicates the set of supported protocols (Section 6.1 of SVCB).  There is no default protocol, so the "no-default-alpn" key does not apply, and the "alpn" key MUST be present. </ins> If the protocol set contains any HTTP versions (e.g. "h2", "h3"), then the record indicates support for DNS over HTTPS DOH, and the 4.2.  <ins> This key is used to indicate the target port for connection ((Section 6.2 of SVCB)).  If omitted, the client SHALL use the default port for each transport protocol (853 for DNS over TLS DOT, 443 for DNS over HTTPS). </ins> This key is automatically mandatory if present.  (See Section 7 of SVCB for the definition of "automatically mandatory".)