After performing [[ https://en.wikipedia.org/w/index.php?title=Template:No_admin_backlog/doc&type=revision&diff=887206381&oldid=886421715&diffmode=source | this edit ]] using rollback on the english wikipedia, I saw an error at the "Action complete" page ([[ https://en.wikipedia.org/w/index.php?title=Template:No_admin_backlog/doc&action=rollback&from=2405%3A4800%3A58C7%3A4B5%3A314D%3A6E43%3A1361%3A78E6&token=f47c1e30806b436a3c1441f09d6c83c35c86039b%2B%5C | here ]]). Screenshots of the page, and of the html that caused it to display, are attached. I believe it is related to https://github.com/wikimedia/operations-mediawiki-config/blob/master/wmf-config/CommonSettings.php#L517, since the error reports that $wmgUsePagedTiffHandler is undefined, and I can't find it mentioned previously in that file.
{F28364679}
{F28364678}