How to restore the precedent session from a sessionstore.bak file

This is a cross-post from https://support.mozilla.org/en-US/questions/947856

When I tried to open firefox it automatically updated and supressed the sessionstore.js file. I saved the sessionstore.bak into another folder, closed mozilla, changed the extension bak to js in the "profiles" folder of firefox and opened it again but nothing happened. Though the sessionstore.bak file is 13Ko big and seems to contain all the links of my previous session.

How could I force Firefox to start a session using the information in the sessionstore.bak or .js file as it should?

My Answer

1. Open a sessionstore.js file in a browser. It can be a different browser (Chrome) if you like.
2. Open Firebug/Inspector.
3. Type:
   eval("ss = "+document.body.innerHTML.replace("<pre>", "").replace("</pre>", ""));
4. Type:
   

   for (var i = 0; i < ss.windows[0].tabs.length; i++) { var ent = ss.windows[0].tabs[i].entries; var last = ent[ent.length-1]; document.write("<a href="+last.url+">"+last.url+"</a><br />"); }

Enjoy all tabs from sessionstore on your screen. You only need to Ctrl-click them one by one.

Addendum: In case you see an error "TypeError: ss.windows[0] is undefined" you need to try again but replace all references of "ss.windows" to "ss.closedWindows". This depends on the contents of your sessionstore.bak file.