Security for Confluence Data Center scans line-by-line, so newline matchers will never be matched. Existing rules which contain newlines will continue to run, but cannot be edited without removing the newline characters.
List of disallowed sequences:
-
\n,\x0a,\x0A,\u000a,\u000A -
\r,\x0d,\x0D,\u000d,\u000D -
\R