I recently debugged an issue where my custom Looper Provider wasn’t working. It turned out that the key used in the cs_looper_custom_{$key} filter in PHP and the corresponding Key field in the Cornerstone Builder are not only case-sensitive , but they also seem to require lowercase formatting (e.g., my_custom_provider_key ) . My original key, using PascalCase, didn’t work until I switched it to all lowercase.
While this aligns with common WordPress coding standards for hook names , it isn’t explicitly mentioned in the Looper API documentation for custom provider keys. This small detail can be quite time-consuming to debug as it’s easily overlooked.
A short note clarifying this in your docs would save a lot of frustration for other users.
Thanks for your excellent work on Theme.co, especially the incredibly powerful Custom Providers – they’re truly a killer feature!