I use Firefox on macOS where, to close a tab, you use Cmd-W and Cmd-Q quits the program. W and Q are next to each other so I often accidentally press cmd-Q when I mean to close a tab. In about:config I have browser.tabs.warnOnClose, browser.warnOnQuit and browser.showQuitWarning all set to true, but Cmd-Q still shows no warning. Reading some all blog post, this may be because I have session restore enabled, but restoring tab is not good enough as not everything is restored (for instance if you scrolled down on a page with infinite scrolling, like Twitter). Before Firefox 57 I used an extension to ask for confirmation before closing but that extension is not compatible with Quantum. Is there any way to get the warning again? Alternatively, any way to change the shortcut to close the app? (This may not be possible as Cmd-Q is a OS-wide shortcut with a partiuclar meaning on macOS.)