Is there any way to change Firefox’s default keyboard shortcuts? An extension, perhaps?
I don’t know of any extensions, but I’ve done this manually. The keyboard shortcuts (in fact, much of the visible interface, including menu items) are defined in various .xul files (XML format), zipped up into .jar files in the chrome/ subdirectory of your Mozilla installation. Basically, you find the appropriate command or menu item and add or modify its keyboard shortcut; then zip the .jar back up. (This probably has to be redone after an update.)
Here is an XUL tutorial on keyboard shortcuts.
Nice. Thanks 