#8169 Updating markdown cache should not affect last_updated
If markdown rendering (e.g for a ticket, comment, whatever) does not exceed markdown_cache_threshold it will not save the result to mongo. Later if someone visits the ticket page, and the markdown rendering takes longer and is saved to mongo, it currently updates last_updated but it shouldn't.
To reproduce this reliably, comment out markdown_cache_threshold in your .ini and create some content. Then set markdown_cache_threshold = 0 and visit the page with the content. The updated date will be changed - as can be seen on your user profile list of projects.
Fix on branch db/8169