rem: BrowserBack(); 
add: switch (pref.getIntPref("browser.backspace_action")) { case 0: BrowserBack(); break; case 1: goDoCommand("cmd_scrollPageUp"); break; } 
context: function BrowserHandleBackspace(){  // The order of seeing keystrokes is this:  // 1) Chrome, 2) Typeahead, 3) [platform]HTMLBindings.xml  // Rather than have typeaheadfind responsible for making VK_BACK   // go back in history, we handle backspace it here as follows:  // When backspace is pressed, it might mean back  // in typeaheadfind if that's active, or it might mean back in history  var typeAhead = null;  const TYPE_AHEAD_FIND_CONTRACTID = "@mozilla.org/typeaheadfind;1";  if (TYPE_AHEAD_FIND_CONTRACTID in Components.classes) {    typeAhead = Components.classes[TYPE_AHEAD_FIND_CONTRACTID]                .getService(Components.interfaces.nsITypeAheadFind);  }    if (!typeAhead || !typeAhead.backOneChar()) {    BrowserBack();  }}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/f6e1972efa5e42d95f8255bdb3031d2e3debbfdb/navigator.js/clean/suite/browser/navigator.js