arrey key exists error in class.mla-shortcode-support.php

Hello, my site gives me an error:
Warning: array_key_exists() expects parameter 2 to be array, null given in /... my adress .../wordpress/wp-content/plugins/media-library-assistant/includes/class-mla-shortcode-support.php on line 798

This line appears multiple times on top of every page the plugin is involved. The number of appereances depends. I tried to reduce the call to just `mla_gallery post_parent=all´
that gives me two lines, but same page with
`mla_gallery post_parent=all tag=’150920′ mla_alt_shortcode=gallery type=”rectangular” meta_key=”Timestamp” orderby=meta_value order=ASC link=’Lightbox’ ´

gives me the identical error line for seven times.

The error appears too, while loading the wp-admin plus the line:
Warning: Cannot modify header information – headers already sent by (output started at ///same as error above///) in …/wp-admin/admin-header.php on line 9

Besides of that error, the plugin is working as good as ever.
My site is running on PHP 7.3.23 and my site is currently in maintenance mode

• This topic was modified 4 years, 10 months ago by gekow.
• This topic was modified 4 years, 10 months ago by gekow.
• This topic was modified 4 years, 10 months ago by gekow.

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