Joomla module chrome defines the wrapper around a module’s content. It can control the container, heading and CSS classes.
Difference from a module layout
The module layout generates inner content, while chrome supplies surrounding markup. Changing Joomla module chrome can therefore remove a heading or wrapper even when the module itself works correctly. Available styles depend on the template.
Diagnosing output
Check the module style option and the style requested by the template position, then inspect the final Joomla HTML. A missing class or heading can originate in the wrapper rather than module data or CSS.
Joomla module chrome integrates a block with site presentation. Distinguish its outer wrapper from the module’s internal layout.