Here's one in case anyone is pulling out their hair trying to work out
why they get the following message in their apache error.log:
PHP Warning: Module 'Zend Optimizer' already loaded in Unknown on line 0
PHP Warning: Zend Optimizer: module registration failed! in Unknown on
line 0
It seems that dbg somehow conflicts with Zend in a XAMPP installation,
and needs to be installed as a Zend extension. Here are the instructions:
Don't believe installation instructions 😉