When we use a wordpress theme then some time we ignore the compatibility and security of Script. But we are not sure that third party scripts are 100% compatible with wordpress or Secure with no hole that might expose you.
Theme compatibility of theme can be checked by plugins. And of these plugins are used by the theme review team if wordpress.org. These plugins are used to check the code compatibility of theme with wordpress and find any bug.
Theme-Check
A free plugin used by developers and it is used by the theme review team of wordpress.org. It help us to check that if your theme is compatible with all the latest wordpress standards.
Log Deprecated Notices
A free plugin from wordpress.org for developer. It is useful for checking deprecated functions, files and function arguments that the active theme might be using.
Debogger
It is cool and useful it not only debug theme and find error but also checks the loaded page and validate it
When we are building a theme we have to look and check some points to lower the error count in your logs when checking the final result.
1.Sometime we got help from other sources they use some built in functions that are Deprecated .So please check these functions on Codex and if function is deprecated Then don’t use it.
2. Mostly Developer don’t code in quality way. They don’t write code in right place. That why they Lose the quality of their code. So no matter what you do ,you must do right and use right code in right place.
WordPress Development has some rules and approaches, Make sure you know what they are and when to use them and make sure you are not missing something important.