Running old plugins and themes is not smart. Most of us don’t have time to go through each line of code to find every deprecated function. The good news is you can use one of these scripts to automate the process:
Plugin Inspector: scans plugins for deprecated WordPress functions. It also scans files for unsafe code snippets. You will have path, line number, and everything you need to take action.
WP Mechanic: a malware and deprecated function scanner. It can also answer questions you may have about WP coding.
Log Deprecated Notices: as the name suggests, this plugin logs when deprecated files and functions are called. It also tracks incorrect function usage.
Have you found other tools to ID deprecated and unsafe WP functions? Please share them here.