Hierarchy Debugger:
controllers/app.php
controllers/index.php
controllers/singular.php
controllers/single.php
controllers/single-attachment.php
controllers/single-attachment-pros-for-heroes-image-healthcare-workers-in-scrubs-enjoying-gift-of-food-999x563-1.php
controllers/attachment.php
controllers/image_png.php
controllers/png.php
controllers/image.php