Found the following validation problem for the NEWS.Rd HTML conversion:
NEWS.html:93:1 (inst/NEWS.Rd:39): Warning: <h4> anchor "Features" already defined
NEWS.html:108:1 (inst/NEWS.Rd:47): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:126:1 (inst/NEWS.Rd:57): Warning: <h4> anchor "Features" already defined
NEWS.html:140:1 (inst/NEWS.Rd:63): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:155:1 (inst/NEWS.Rd:71): Warning: <h4> anchor "Features" already defined
NEWS.html:170:1 (inst/NEWS.Rd:80): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:188:1 (inst/NEWS.Rd:90): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:204:1 (inst/NEWS.Rd:100): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:248:1 (inst/NEWS.Rd:127): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:259:1 (inst/NEWS.Rd:132): Warning: <h4> anchor "New-features" already defined
NEWS.html:277:1 (inst/NEWS.Rd:141): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:292:1 (inst/NEWS.Rd:149): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:304:1 (inst/NEWS.Rd:155): Warning: <h4> anchor "New-features" already defined
NEWS.html:320:1 (inst/NEWS.Rd:164): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:333:1 (inst/NEWS.Rd:171): Warning: <h4> anchor "New-features" already defined
NEWS.html:349:1 (inst/NEWS.Rd:181): Warning: <h4> anchor "New-features" already defined
NEWS.html:364:1 (inst/NEWS.Rd:189): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:375:1 (inst/NEWS.Rd:194): Warning: <h4> anchor "New-features" already defined
NEWS.html:392:1 (inst/NEWS.Rd:204): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:403:1 (inst/NEWS.Rd:209): Warning: <h4> anchor "New-features" already defined
NEWS.html:418:1 (inst/NEWS.Rd:218): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:436:1 (inst/NEWS.Rd:228): Warning: <h4> anchor "New-features" already defined
NEWS.html:451:1 (inst/NEWS.Rd:237): Warning: <h4> anchor "New-features" already defined
NEWS.html:462:1 (inst/NEWS.Rd:242): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:477:1 (inst/NEWS.Rd:250): Warning: <h4> anchor "New-features" already defined
NEWS.html:495:1 (inst/NEWS.Rd:258): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:513:1 (inst/NEWS.Rd:268): Warning: <h4> anchor "New-features" already defined
NEWS.html:524:1 (inst/NEWS.Rd:273): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:539:1 (inst/NEWS.Rd:281): Warning: <h4> anchor "New-features" already defined
NEWS.html:562:1 (inst/NEWS.Rd:292): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:580:1 (inst/NEWS.Rd:302): Warning: <h4> anchor "New-features" already defined
NEWS.html:596:1 (inst/NEWS.Rd:311): Warning: <h4> anchor "New-features" already defined
NEWS.html:611:1 (inst/NEWS.Rd:319): Warning: <h4> anchor "New-features" already defined
NEWS.html:631:1 (inst/NEWS.Rd:329): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:655:1 (inst/NEWS.Rd:343): Warning: <h4> anchor "New-features" already defined
NEWS.html:670:1 (inst/NEWS.Rd:352): Warning: <h4> anchor "Bugfixes" already defined
NEWS.html:686:1 (inst/NEWS.Rd:361): Warning: <h4> anchor "New-features" already defined
NEWS.html:714:1 (inst/NEWS.Rd:373): Warning: <h4> anchor "Bugfixes" already defined