A quick search says this is an error with Javascript. Check your Java plugin version for Firefox here: https://www.mozilla.org/en-GB/plugincheck/. If you do not have Java installed, you can get it here: http://java.com/en/. PS. Also found this: http://stackoverflow.com/questions/12267903/firefox-typeerror-localstorage-is-null#12269453.

You can check if DOM Storage is enabled. *http://kb.mozillazine.org/dom.storage.enabled You can open the <b>about:config</b> page via the location/address bar. You can accept the warning and click "I'll be careful" to continue. *http://kb.mozillazine.org/about:config ---- This issue can be caused by corrupted cookies or cookies that are blocked. *check the permissions on the about:permissions page and in "Tools > Page Info > Permissions" *https://support.mozilla.org/kb/fix-login-issues-on-websites-require-passwords Clear the cache and remove cookies only from websites that cause problems. "Clear the Cache": *Firefox/Tools > Options > Advanced > Network > Cached Web Content: "Clear Now" "Remove Cookies" from sites causing problems: *Firefox/Tools > Options > Privacy > "Use custom settings for history" > Cookies: "Show Cookies" Start Firefox in <u>[[Safe Mode|Safe Mode]]</u> to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem. *Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance *Do NOT click the Reset button on the Safe Mode start window *https://support.mozilla.org/kb/Safe+Mode *https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes