Found the following validation problem for the NEWS.Rd HTML conversion:
NEWS.html:45:1 (inst/NEWS.Rd:24): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:60:1 (inst/NEWS.Rd:32): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:76:1 (inst/NEWS.Rd:41): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:103:1 (inst/NEWS.Rd:55): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:130:1 (inst/NEWS.Rd:69): Warning: <h4> anchor "Misc" already defined
NEWS.html:149:1 (inst/NEWS.Rd:80): Warning: <h4> anchor "Misc" already defined
NEWS.html:164:1 (inst/NEWS.Rd:88): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:183:1 (inst/NEWS.Rd:99): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:224:1 (inst/NEWS.Rd:123): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:237:1 (inst/NEWS.Rd:130): Warning: <h4> anchor "Tweaks" already defined
NEWS.html:252:1 (inst/NEWS.Rd:138): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:263:1 (inst/NEWS.Rd:143): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:287:1 (inst/NEWS.Rd:159): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:299:1 (inst/NEWS.Rd:165): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:328:1 (inst/NEWS.Rd:179): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:343:1 (inst/NEWS.Rd:187): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:371:1 (inst/NEWS.Rd:205): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:388:1 (inst/NEWS.Rd:215): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:408:1 (inst/NEWS.Rd:226): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:428:1 (inst/NEWS.Rd:238): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:444:1 (inst/NEWS.Rd:247): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:456:1 (inst/NEWS.Rd:253): Warning: <h4> anchor "Tweaks" already defined
NEWS.html:468:1 (inst/NEWS.Rd:259): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:487:1 (inst/NEWS.Rd:270): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:513:1 (inst/NEWS.Rd:287): Warning: <h4> anchor "Tweaks" already defined
NEWS.html:527:1 (inst/NEWS.Rd:293): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:549:1 (inst/NEWS.Rd:305): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:570:1 (inst/NEWS.Rd:318): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:588:1 (inst/NEWS.Rd:328): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:608:1 (inst/NEWS.Rd:340): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:624:1 (inst/NEWS.Rd:349): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:643:1 (inst/NEWS.Rd:358): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:660:1 (inst/NEWS.Rd:368): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:679:1 (inst/NEWS.Rd:379): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:696:1 (inst/NEWS.Rd:390): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:714:1 (inst/NEWS.Rd:398): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:747:1 (inst/NEWS.Rd:417): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:767:1 (inst/NEWS.Rd:425): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:782:1 (inst/NEWS.Rd:433): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:807:1 (inst/NEWS.Rd:444): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:823:1 (inst/NEWS.Rd:453): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:834:1 (inst/NEWS.Rd:458): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:849:1 (inst/NEWS.Rd:466): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:869:1 (inst/NEWS.Rd:477): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:884:1 (inst/NEWS.Rd:485): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:899:1 (inst/NEWS.Rd:494): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:914:1 (inst/NEWS.Rd:502): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:929:1 (inst/NEWS.Rd:510): Warning: <h4> anchor "Misc" already defined
NEWS.html:941:1 (inst/NEWS.Rd:514): Warning: <h4> anchor "Misc" already defined
NEWS.html:953:1 (inst/NEWS.Rd:518): Warning: <h4> anchor "Misc" already defined
NEWS.html:965:1 (inst/NEWS.Rd:522): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:983:1 (inst/NEWS.Rd:531): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1000:1 (inst/NEWS.Rd:538): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:1015:1 (inst/NEWS.Rd:546): Warning: <h4> anchor "Misc" already defined
NEWS.html:1027:1 (inst/NEWS.Rd:550): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1042:1 (inst/NEWS.Rd:558): Warning: <h4> anchor "Misc" already defined
NEWS.html:1054:1 (inst/NEWS.Rd:562): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:1072:1 (inst/NEWS.Rd:571): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1095:1 (inst/NEWS.Rd:584): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1111:1 (inst/NEWS.Rd:593): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1123:1 (inst/NEWS.Rd:599): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:1138:1 (inst/NEWS.Rd:608): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1154:1 (inst/NEWS.Rd:617): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1210:1 (inst/NEWS.Rd:643): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1229:1 (inst/NEWS.Rd:653): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:1265:1 (inst/NEWS.Rd:677): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1279:1 (inst/NEWS.Rd:683): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:1290:1 (inst/NEWS.Rd:688): Warning: <h4> anchor "DEPRECATED-+26-DEFUNCT" already defined