* Clean up javascript.
* Return HTTP 422 instead of HTTP 500 on "you have already voted for
this post" errors.
* In json/xml error responses, return the error message in the `message`
field, not `reason`.
* In json/xml success responses, return the post itself instead of a
plain `{ success: true }` object.
* Simplify code.
* Show backtraces for all users, not just builders.
* Show backtraces only for unexpected server errors (status 5xx), not
for normal client errors (status 4xx).
* Log expected errors at info level (reduce noise in production logs).
This causes the browser to prefetch the next page in a search, which may
make browsing seem faster to the end user, but it effectively doubles
the load on the server.
Avoid some queries used in wiki page excerpts:
* Only try to load the artist if the tag is an artist tag.
* Avoid using `exists?` queries for wiki pages.
* Bugfix: don't show wiki excerpts for deleted wikis.
* When creating an artist by clicking the '?' next to the artist tag in
the tag list, prefill the new artist form by finding the artist's last
upload and fetching its source data.
Previously we filled the urls with the source of the artist's last
upload, which was wrong because it was usually a direct image URL (#3078).
* Fix the other names field not escaping spaces within names to underscores.
* Fix the other names field being potentially prefilled with duplicate names.
https://danbooru.donmai.us/forum_topics/9127?page=265#forum_post_153180:
> I'm not sure how to reproduce this, but sometimes on the upload page
> when I click the button to pop out the tag box, the screen scrolls up to
> the picture but the box doesn't pop out, and I have to scroll back down
> and click it again
https://danbooru.donmai.us/forum_topics/9127?page=266#forum_post_153183:
> Yes, this was brought up by Unbreakable on Discord a while back. It's
> due to the fact that the event handler that pops out the dialog box has
> not yet been bound by the time you click it. Since that clickable
> control has an empty anchor link of "#" which goes nowhere, it therefore
> redirects the user to the top of the page.
