Searching the contents of larger pages such as <http://bugzilla.gnome.org/enter_bug.cgi> can be quite slow. On my system, it takes several seconds for the screen to update after I press Ctrl+F and type 'epiphany'.

On closer investigation, it seems that the major slowdown comes from the browser highlighting every occurance of the character 'e', and this takes a couple of seconds. Typing 'p' is much quicker, and subsequent letters tend towards being quick enough (though still causing a noticeable delay).