Last modified: 2012-05-14 10:15:40 UTC
$wgEnableTooltipsAndAccesskeys was introduced by Domas in 1.16 r55984 (later renamed with r56068) for performance reason. http://www.mediawiki.org/wiki/Manual:$wgEnableTooltipsAndAccesskeys It is enabled on enwiki so I am not sure we need that global anymore
Being bold and phasing it out with r103688