JUCMCONTENT-CLASS-001

JUcmContent

JUcmContent class name

JUcmContent is a Joomla 3 global class. Joomla 4 still has an alias. Joomla 5 needs the Behaviour – Backward Compatibility plugin. Native Joomla 6 does not load that alias — you get Class "JUcmContent" not found.

JUcmContentJoomla\CMS\UCM\UCMContent

Dies at Joomla 5 → 6J3: Works nativelyJ4: Alias (old name still resolves)J6: Removed — fatalBC plugin: covers the class nameMechanical renameJoomla API

What you will see

  • Class "JUcmContent" not found
  • Class 'JUcmContent' not found
  • Failed to open stream: JUcmContent

Symptoms people search

white screen after disabling compatibility plugin · class not found on Joomla 6 · works on Joomla 5 until I turn off backward compatibility

Replace this code

Swap JUcmContent for Joomla\CMS\UCM\UCMContent.

Joomla 3

Remove or stop calling this

JUcmContent::getInstance();
// or new JUcmContent()

Joomla 4 / 6

Use this instead

use Joomla\CMS\UCM\UCMContent;

// Call the namespaced class. Do not keep the J prefix.

How to fix it

  1. 1Add a use statement for Joomla\CMS\UCM\UCMContent.
  2. 2Replace every JUcmContent with the short class name from that use line.
  3. 3Disable Behaviour – Backward Compatibility on a Joomla 5 staging site. If it fatals, this class is still in the code.

Also known as

JUcmContent · Joomla\CMS\UCM\UCMContent · class alias · J prefix

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