Added

• Accept mailto, tel, sms, and other link prefixes by default in the insert link toolbar button #2525.
• validateLink in QuillToolbarLinkStyleButtonOptions to allow overriding the link validation #2525.

Fixed

• Improve doc comment of customLinkPrefixes in QuillEditor #2525.

Changed

• Deprecate linkRegExp in favor of the new callback validateLink #2525.