I don't know if this behavior is intended or a bug.

What I expected

Keys usually don't contain special characters.

What happened instead

The box ID meta key used by Papi when none is provided can contain accents, quotes, etc.

Steps to reproduce

var_dump( strtolower( papi_f( papi_underscorify( papify( 'string with quotes’ and accènts' ) ) ) ) );

What versions of softwares are you using?

• Papi: 3.1.18
• WordPress: 4.7.2