J3.x:Module random image PHP Error after 3.8.8

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Errors reported

Fatal error: Using $this when not in object context in .../modules/mod_random_image/tmpl/default.php on line 16

Versions affected

General Information

This pertains only to Joomla! version(s): 3.8.8

What is the cause

Modules don't have $this context, so can't call $this->escape(). Escape output using htmlspecialchars() instead.

How to fix

Apply this patch https://github.com/joomla/joomla-cms/pull/20533/files