Document that regex_pcre2 should be a drop-in replacement.

Author: sadiepowell

docs/4/breaking-changes.md

@@ -42,7 +42,7 @@ title: v4 Breaking Changes
 
 - The nopartmsg module has been moved to inspircd-contrib. In order to upgrade either remove this module from your configuration, run `./modulemanager install nopartmsg` to install it, or migrate to [the muteban module](/4/modules/muteban) which now also applies to part messages.
 
-- The regex_pcre module has been moved to inspircd-contrib. In order to upgrade either migrate remove this module from your configuration, run `./modulemanager install regex_pcre` to install it, or migrate to [the regex_pcre2 module](/4/modules/regex_pcre2).
+- The regex_pcre module has been moved to inspircd-contrib. In order to upgrade either remove this module from your configuration, run `./modulemanager install regex_pcre` to install it, or migrate to [the regex_pcre2 module](/4/modules/regex_pcre2) which also provides the "pcre" regex engine so it should be a drop-in replacement.
 
 - The regex_tre module has been moved to inspircd-contrib. In order to upgrade either remove this module from your configuration, run `./modulemanager install regex_tre` to install it, or migrate to [the regex_stdlib module](/4/modules/regex_stdlib).