Understanding Scan Sources

The scanner checks for media usage across every place WordPress commonly references a file.

What gets checked

Post and page content, Featured Images, direct attachment relationships (files uploaded into a post), custom fields / post meta, Advanced Custom Fields (ACF) values when ACF is active, widgets (including block-based widgets), Theme Customizer settings (logo, background, header image), and the Site Icon.

Turning sources on or off

Each of these sources can be individually enabled or disabled from the Settings screen, so you can tailor exactly what counts as “in use” for your site.