A column page.page_no_title_convert is visible on ToolLabs (at least on dewiki_p). I have not found any extension using this field.
There is a entry in the HISTORY, a proposed schema change which seems not fully implemented:
Should be dropped, because it is unused. If this is not visible on production please move the task to ToolLabs. Thanks.
[x] s1 (doesn't have this column)
[x] eqiad T86342#4984107
[x] eqiad progress T86342#4987658
[x] eqiad progress T86342#4979690
[x] eqiad progress T86342#4990469
[x] s8 (doesn't have this column)
[x] wikitech (doesn't have this column)
ALTER TO RUN:
ALTER TABLE page DROP COLUMN IF EXISTS page_no_title_convert;