Jon Robson wrote:
To solve validness I'd suggest creating styles for this in MediaWiki:Common.css and on a regular basis running reports to surface which articles use the text-align property. It would be great to have a dedicated wiki page linking to these articles and asking editors to fix them. It would give people who care about Wikipedia an easy way to contribute.
I have a similar problem in mobile - at some point I'd like us to deprecate use of the style attribute in wikitext in favour of using stylesheets and the class attribute which is much more manageable and would be interested in whatever solution you come to here.
Finding specific text strings like these requires scanning XML dumps. There are a few projects dedicated to this on various wikis. English examples:
* https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Check_Wikipedia * https://en.wikipedia.org/wiki/Wikipedia:Dump_reports
Scanning dumps (or really dealing with them in any form) is pretty awful. There's been some brainstorming in the past for how to set up a system where users (or operators) could run arbitrary regular expressions on all of the current wikitext regularly, but such a setup requires _a lot_ of anything involved (disk space, RAM, bandwidth, processing power, etc.). Maybe one day Labs will have something like this.
It's a well-known fact that if you give Wikimedians lists of things to do, they will eventually get done. I've done this for years with https://en.wikipedia.org/wiki/Wikipedia:Database_reports.
MZMcBride