Debug trace for WordPress, including action and filter tracing
Kint is a modern and powerful PHP debugging helper, which requires zero-setup and replaces var_dump(), print_r() and debug_backtrace().
Display debug backtraces for every error generated by PHP.
Kint Debugger makes debugging and dumping variables a more pleasant experience. Kint Debugger integrates seamlessly with the Debug Bar plugin.
A Debug Bar plugin that lets you trace what plugins are causing database queries.
Krumo is a debug tool able of collapsing array and object values so that it takes less space and let us see only what we really need from complex data