Found the following validation problem for the NEWS.Rd HTML conversion:
NEWS.html:80:1 (inst/NEWS.Rd:36): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:101:1 (inst/NEWS.Rd:47): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:117:1 (inst/NEWS.Rd:55): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:134:1 (inst/NEWS.Rd:64): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:152:1 (inst/NEWS.Rd:72): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:164:1 (inst/NEWS.Rd:78): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:198:1 (inst/NEWS.Rd:94): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:225:1 (inst/NEWS.Rd:109): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:238:1 (inst/NEWS.Rd:116): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:255:1 (inst/NEWS.Rd:125): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:274:1 (inst/NEWS.Rd:136): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:300:1 (inst/NEWS.Rd:150): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:330:1 (inst/NEWS.Rd:166): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:364:1 (inst/NEWS.Rd:186): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:378:1 (inst/NEWS.Rd:192): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:409:1 (inst/NEWS.Rd:207): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:430:1 (inst/NEWS.Rd:220): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:458:1 (inst/NEWS.Rd:234): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:473:1 (inst/NEWS.Rd:241): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:493:1 (inst/NEWS.Rd:255): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:510:1 (inst/NEWS.Rd:264): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:526:1 (inst/NEWS.Rd:272): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:542:1 (inst/NEWS.Rd:282): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:555:1 (inst/NEWS.Rd:290): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:570:1 (inst/NEWS.Rd:297): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:591:1 (inst/NEWS.Rd:308): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:606:1 (inst/NEWS.Rd:315): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:619:1 (inst/NEWS.Rd:322): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:631:1 (inst/NEWS.Rd:328): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:646:1 (inst/NEWS.Rd:335): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:664:1 (inst/NEWS.Rd:345): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:705:1 (inst/NEWS.Rd:366): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:716:1 (inst/NEWS.Rd:371): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:733:1 (inst/NEWS.Rd:378): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:760:1 (inst/NEWS.Rd:389): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:775:1 (inst/NEWS.Rd:396): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:794:1 (inst/NEWS.Rd:405): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:826:1 (inst/NEWS.Rd:423): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:848:1 (inst/NEWS.Rd:435): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:870:1 (inst/NEWS.Rd:445): Warning: <h4> anchor "BUG-FIXES" already defined
NEWS.html:892:1 (inst/NEWS.Rd:455): Warning: <h4> anchor "NEW-FEATURES" already defined
NEWS.html:916:1 (inst/NEWS.Rd:469): Warning: <h4> anchor "USER-VISIBLE-CHANGES" already defined
NEWS.html:945:1 (inst/NEWS.Rd:484): Warning: <h4> anchor "BUG-FIXES" already defined