restoring lost tabs in firefox

Every once in a while (often), something happens and the “Restore session” option in firefox disappears (right now it is june 2016), usually this happens after a crash where i try to re open firefox early or when computer hangs then i do something stupid, if you just opened firefox, keep it open, then go to C:\Users\techg\AppData\Roaming\Mozilla\Firefox\Profiles\8xve5flx.default (Or whatever your profile folder is named), and WITH YOUR FIREFOX STILL OPEN, copy the file sessionstore.js (back it up), Now close firefox, your original might have reset to a small file size as soon as you close firefox, Now, the tabs are all stored in sessionstore.js.bak (or whatever you called the copy), so delete the one you have, and copy this file back in it’s place.

With that done, it is editing time

The bad copy starts like this

{"version":["sessionrestore",1],"windows":[{"tabs":[{"entries":[{"url":"about:home","title":"Mozilla Firefox Start Page","charset":"","ID":716087720,"docshellID":11510,"docIdentifier":13,"persist":true}],"lastAccessed":1465298115431,"hidden":false,"attributes":{},"userContextId":0,"index":1,"image":"chrome://branding/content/icon32.png"}],

delete some text (“version”:[“sessionrestore”,1],) to make it look like this

{"windows":[{"tabs":[{"entries":[{"url":"about:home","title":"Mozilla Firefox Start Page","charset":"","ID":716087720,"docshellID":11510,"docIdentifier":13,"persist":true}],"lastAccessed":1465298115431,"hidden":false,"attributes":{},"userContextId":0,"index":1,"image":"chrome://branding/content/icon32.png"}],

Now, open your firefox browser, and you should see the restore button come back up.