For those who updated Magz II the same error with the size of the image from version 1.0.4 to 1.0.5 also happened in the actualization of version 1.0.5 to 1.0.6
Just follow the steps:
templates / ja_magz_ii / html / layouts / joomla / content / image / image.php
Search:
$size = $params->get('size', 'big');
correct:
$size = $params->get('size');
See the solution link
https://www.joomlart.com/forums/topic/error-update-1-0-4-to-1-0-5
hugs