undefined array showing on wp-admin/post-new.php

Warning: Undefined array key “awac_meta_metabox_nonce” in /home/XXXXXXXXX/the5krunner.com/wp-content/plugins/add-widget-after-content/add-widget-after-content.php on line 254

I’ve used widget after content for several years:

I have the latest php version and wordpress and its plugins are all up to date.

if i rollback widget after to 2.4.6 the error goes away

any help appreciated in sorting that error.

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