Lifehacker reader James was having trouble getting the Find feature in Firefox to work properly, but a simple modification fixed his problems. James writes:
When you hit Ctrl+F to bring up the Quickfind menu and start typing, by default it is case-sensitive. This is an incredibly bizarre feature for Mozilla to have enabled by default, eg searching the Lifehacker homepage for even "lifehacker" by default brings no results. To disable this feature navigate to about:config in the address bar and head to accessibility.typeaheadfind.casesensitive - ironically simply typing "case" in the filter bar does the trick. By default this is an integer set to 1, simply double click and change its value to 0 and you're on your way.
I'm not sure this is actually the default setting -- on my copy of Firefox everything was already working fine, so it might be one of those weird extension-dependent things -- but it's a useful hack if things are going wrong. Thanks James!