Theme triggers errors due to usage of outdated WordPress functions or hooks.
Theme Uses Deprecated Functions
Key Points: Errors or warnings appear due to old functions removed from newer WordPress versions.
You activate the theme, and the error log explodes. “Function xyz is deprecated…” or “Call to undefined function…” — it’s like reading WordPress archaeology. Your theme hasn’t aged well.
🛠️ Where It Fails
- Functions removed in major WP updates (like
get_page_by_title()) - Old PHP versions used in the code
- Custom widgets using outdated APIs
🧪 What to Do
- Turn on
WP_DEBUGto trace deprecated calls - Update or replace the theme
- If custom, refactor using the updated WordPress Codex
⚠️ Tip
Always test themes on the latest WP version before going live. And beware of “premium” themes that haven’t been updated in years.