In https://en.wikipedia.org/w/index.php?title=Star-Spangled_Banner_(flag)&curid=7246021&diff=826054878&oldid=812171510&diffmode=visual the word 'the' is inserted in two paragraphs, but in the second it is show as <del>at</del><ins>at the</ins>, whereas in the first it is just <ins>the</ins>.
Update: This is a smaller (minimal?) test case:
foo quux at bar
->
foo, quux at the bar