MY_Session file to write custom functions

Hello,

For set_flashdata() i need to write a custom filter, but creating MY_Session.php in the libraries folder doesn't seem to work. Does it also requires the fullpath for this, i.e. 'Session/drivers/' ?

Thanks in advance

You can't extend it that way, it's a driver. Here's the user docs for that part.
https://codeigniter.com/user_guide/libra...om-drivers