Debug Error

Hello,

Great Plugin!

Debug bar is reporting the following php warning.
Can it be fixed?

Warning array_merge(): Argument #1 is not an array
1
wp-content/plugins/pdf-light-viewer-pro/controllers/PdfController.php:110 array_merge()
wp-content/plugins/pdf-light-viewer-pro/controllers/PdfController.php:110
PdfLightViewerPro_PdfController::cmb_metaboxes()
Unknown location
apply_filters(‘cmb_meta_boxes’)
wp-content/plugins/easy-heads-up-bar/lib/cmb/init.php:41
ehb_initialize_cmb_meta_boxes()
Unknown location
do_action(‘init’)
wp-settings.php:393

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