[#1403] Describe breaking change in comment

webui/src/app/forms/shared-network-form.ts

@@ -309,7 +309,11 @@ export class SharedNetworkFormState {
             })
         }
         // If user selected or unselected DHCP servers of a certain kind it is a
-        // breaking change.
+        // breaking change. In the DHCPv4 case we don't treat the transition from
+        // non-DHCPv4 to DHCPv4 case as a breaking change because, by defeault, we
+        // assume DHCPv4 case when no servers are initially selected. In this case
+        // the form remains unchanged after selecting the first server when new
+        // shared network is defined.
         const breakingChange = (this._dhcpv4 && !dhcpv4) || this._dhcpv6 !== dhcpv6
 
         // Remember new states.