PHP Fatal error: Uncaught TypeError: Cannot access offset of type string on string in Stack trace:\n#0 [internal function]: img_caption_shortcode()
You’re mis-using the caption shortcode here You can fix it by adding a width option, which is required per the official documentation In any case, this is also likely a bug in WordPress (misusing a shortcode shouldn’t result in a PHP Fatal Error). See the following bug report: https://core.trac.wordpress.org/ticket/59206