Found the following validation problem for the NEWS.Rd HTML conversion:
NEWS.html:1200:1 (inst/NEWS.Rd:598): Warning: missing </ul> before </div>
NEWS.html:40:1 (inst/NEWS.Rd:12): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:55:1 (inst/NEWS.Rd:19): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:70:1 (inst/NEWS.Rd:26): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:85:1 (inst/NEWS.Rd:33): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:100:1 (inst/NEWS.Rd:40): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:131:1 (inst/NEWS.Rd:55): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:146:1 (inst/NEWS.Rd:62): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:168:1 (inst/NEWS.Rd:74): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:180:1 (inst/NEWS.Rd:80): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:196:1 (inst/NEWS.Rd:88): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:211:1 (inst/NEWS.Rd:95): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:230:1 (inst/NEWS.Rd:104): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:282:1 (inst/NEWS.Rd:132): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:294:1 (inst/NEWS.Rd:138): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:311:1 (inst/NEWS.Rd:147): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:326:1 (inst/NEWS.Rd:154): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:339:1 (inst/NEWS.Rd:161): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:376:1 (inst/NEWS.Rd:184): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:392:1 (inst/NEWS.Rd:192): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:406:1 (inst/NEWS.Rd:200): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:429:1 (inst/NEWS.Rd:211): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:445:1 (inst/NEWS.Rd:219): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:471:1 (inst/NEWS.Rd:233): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:498:1 (inst/NEWS.Rd:246): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:549:1 (inst/NEWS.Rd:272): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:569:1 (inst/NEWS.Rd:281): Warning: <h4> anchor "DEPRECATED-+26-DEFUNCT" already defined
NEWS.html:617:1 (inst/NEWS.Rd:305): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:638:1 (inst/NEWS.Rd:316): Warning: <h4> anchor "DEPRECATED-+26-DEFUNCT" already defined
NEWS.html:659:1 (inst/NEWS.Rd:326): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:671:1 (inst/NEWS.Rd:332): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:682:1 (inst/NEWS.Rd:337): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:703:1 (inst/NEWS.Rd:348): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:721:1 (inst/NEWS.Rd:358): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:743:1 (inst/NEWS.Rd:368): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:755:1 (inst/NEWS.Rd:374): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:772:1 (inst/NEWS.Rd:383): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:783:1 (inst/NEWS.Rd:388): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:810:1 (inst/NEWS.Rd:403): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:829:1 (inst/NEWS.Rd:412): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:842:1 (inst/NEWS.Rd:419): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:858:1 (inst/NEWS.Rd:427): Warning: <h4> anchor "DEPRECATED-+26-DEFUNCT" already defined
NEWS.html:878:1 (inst/NEWS.Rd:436): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:894:1 (inst/NEWS.Rd:444): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:909:1 (inst/NEWS.Rd:451): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:952:1 (inst/NEWS.Rd:469): Warning: <h4> anchor "DEPRECATED-+26-DEFUNCT" already defined
NEWS.html:976:1 (inst/NEWS.Rd:480): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:1009:1 (inst/NEWS.Rd:499): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1021:1 (inst/NEWS.Rd:505): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:1037:1 (inst/NEWS.Rd:513): Warning: <h4> anchor "SIGNIFICANT-USER-VISIBLE-CHANGES" already defined
NEWS.html:1054:1 (inst/NEWS.Rd:522): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1101:1 (inst/NEWS.Rd:547): Warning: <h4> anchor "DEPRECATED-+26-DEFUNCT" already defined
NEWS.html:1123:1 (inst/NEWS.Rd:557): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:1146:1 (inst/NEWS.Rd:570): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:1170:1 (inst/NEWS.Rd:582): Warning: <h4> anchor "NEW-FEATURES" already defined