• [core] Support NoAttribute for XPath #1825
• [core] Jaxen adapter implements document nodes incorrectly #1938
• [core] Test some XPath corner cases #2872 (fixed on PMD6 already)
• [core] Deprecate and Remove XPath 1.0 support #1687
• [core] Deprecate support for List attributes with XPath 2.0 #2451 (fixed on PMD6 already)
• [core] Upgrade Saxon, add XPath 3.1, remove Jaxen #2614
• [core] XPath expressions return handling #1939 (fixed on PMD6 already)
• [xml] jaxen xpath function text() does not return an result for a rule #915 (won't fix)
  • fixed on PMD6 via [xml] Add new XPath rule for xml #3864
• [core] Inconsistent boolean value representation with Jaxen #1244 (won't fix)
• [core] Abstract XPath rulechain conversion using our own XPath parser #1243 (won't fix)
• [core] Make more rules be recognized as rulechain (saxon HE) #3207

• Optional improvements ("nice to have")
  • [core] Make AST method returning nodes accessible as XPath attributes #1171 (won't fix)
  • [java] New Java XPath functions #2917

Remaining tasks

Probably for PMD 7

• [doc] Document XPath API @NoAttribute and @DeprecatedAttribute #4308
• [core] Cleanups in XPath area #4309

Postponed

• [core] Select XPath version in violationSuppressXPath #1676
• [core] Make boolean XPath attributes accessible with their prefix #1170
• [core] Generate XSD for attributes and elements exposed through XPath #2217
• [core] Match abstract types in XPath queries #1787