OpenSearch cleanup; Firefox now sends you to the search page for empty searches instead of the domain root (which may not even be a wiki).
This is done by adding the <moz:SearchForm> extension element with the Special:Search URL.
Removed the 24-character truncation on ShortName... neither Firefox nor IE seems to care about longer names, but both expect the ShortName and <link> title to match, and will think you have a duplicate search provider if they don't match because only one was truncated. (Besides, 24 was longer than the spec's limit of 16 -- why bother limiting at all if not to spec?)
The JSON suggestions are now no longer included in the OpenSearch description if the API is disabled, since the interface won't work.
Generally removed some hardcoded escape-then-stick-vars-in-string-output eww... Extension hooks now have a more general opportunity to alter or replace the OpenSearch URLs by tying into the OpenSearchUrls hook.