Another thing I have been noticing in firefox I was just reminded of is that sometimes when I hit the apostrophe key, the "search this page" bar pops up. Yet another quirk that is really annoying.
WARNING: Useful information ahead. I know, it goes against the premise of the thread...
1. Type about:config into the Firefox address bar and hit the Enter key (or press the “Go” button). This will take you to a special advanced configuration screen.
2. Your cursor should already be blinking happily in the “Filter” text box. If not, click in that text box and type “typeahead” to narrow the options down to only those relating to the Find-As-You-Type feature.
3. Check the line that begins with accessibility.typeaheadfind.autostart. This controls whether the browser will start searching text on a web page as soon as you begin typing, without having to first invoke the “Find” dialog by pressing Control–F or typing a forward-slash. I had disabled this feature in the Firefox options, but for some reason this value was set to “true.”
4. If accessibility.typeaheadfind.autostart has a value of “true” on your machine and you’re experiencing the same bug I was, try double-clicking that row in the about:config interface. This will set it’s value to “false,” which solved the problem for me.