First, im new in ubuntu so please bear with me.
My firefox used to be working normally for the first time i installed ubuntu 13.04. I dont feel did anything wrong, but it suddenly cant be opened via the launcher. When i tried to type "firefox" in the terminal, it shows the very same error like this question.
So, i followed the answer in that question, and voila...its working now :D
However, something is still bothering me. Why is this happened suddenly? The fact that i used chown to make it works again means that the owner of the firefox is changed.
And why this message is still appearing in the terminal although the firefox is working now : GLib-CRITICAL **: g_slice_set_config: assertion `sys_page_size == 0' failed
Thanks for your time :D
That message always appears in the terminal when you open firefox, it's not a problem. I can't quite explain it, but it's a bit like when scammers trying to sell you so-called 'antivirus' in Windows they show you a program which contains a load of normal errors and say that it's not normal. Just forget about it. You probably opened it with root as
sudo
instead ofgksudo
some time by accident which would cause stuff to have different permissions.