One upcoming job ABSOLUTELY requires the use of CodeIgniter.
Normally I get away just lying about using frameworks and then just use PHP the right way, but these motherfuckers pro-actively check your Git commits as they work, so you can't win with them.
Looking through the documentation real quick, I see it's almost identical to Laravel.
So that's how you learn and master a new PHP framework in 2 minutes, and wonder why there are so many of them if they're almost entirely the same anyway.
I explained this before in more detail: https://ryocafe.site/blog/stop-asking-php-framework-skills/