Make Firefox Search Automatically Case Sensitive

The Skinny

In Firefox, open a new page with the location “about:config”. Set the config value accessibility.typeaheadfind.casesensitive to ‘2’.

“What did I just do?!”

The Emacs text editor has a subtle-but-great search feature. An interactive search that is all lower-case is treated as case-insensitive. However, a search that contains any upper-case characters is automatically considered case-sensitive. That is, a search for foo will match any of foo, Foo, FoO and so forth. But a search for Bar will match only Bar, ignoring bar, BAR, etc. Once you get used to it, this can be a great timesaver.

For about:config newbies

In Firefox, open a new tab/window and type about:config into the location bar. Look in the left column for the entry accessibility.typeaheadfind.casesensitive. You can use the “Filter” box at the top of the page to quickly reduce the list to a manageable size. Try typing “find” and see what happens. Once found, double-click on the entry name above, set the value to 2, and close the about:config page. You’re all set! Firefox will now use automatic case-sensitivity for the find and link quick-find features.

Further reading

Documentation on this setting and other about:config entries can be found in the MozillaZine Knowledge Base.