Error occurred in Firefox using TYPOlight version 2.7.
I backed-up my website and re-import the database into my localhost computer. The problem is I cannot enable my website in my localhost. Therefore, the next step is to use the install.php to update the database. Well, it did not work.
I remember that I enabled some options at the backend like the FTP configuration in the settings.
To disable it, I back-up my localconfig.php [mysite/system/config/ localconfig.php], edit and deleted all about the FTP settings.
Then, I re-install using the install.php [mysite/typolight/install.php]
OK, now it’s working.