Memory and Uninstall Errors

When I tried the plugin, I got some errors. When the plugin is activated, it appears to consume a lot of memory on the menu editor page:

[27-Jun-2020 10:38:27 UTC] PHP Fatal error:  Allowed memory size of 268435456 bytes exhausted (tried to allocate 303104 bytes) in /path/to/site/wp-includes/wp-db.php on line 2024
[27-Jun-2020 10:38:27 UTC] PHP Stack trace:
[27-Jun-2020 10:38:27 UTC] PHP   1. {main}() /path/to/site/wp-admin/admin-ajax.php:0
[27-Jun-2020 10:38:27 UTC] PHP   2. do_action() /path/to/site/wp-admin/admin-ajax.php:175
[27-Jun-2020 10:38:27 UTC] PHP   3. WP_Hook->do_action() /path/to/site/wp-includes/plugin.php:478
[27-Jun-2020 10:38:27 UTC] PHP   4. WP_Hook->apply_filters() /path/to/site/wp-includes/class-wp-hook.php:311
[27-Jun-2020 10:38:27 UTC] PHP   5. HME_MENU_EDITOR\HMEMenuEditor->ajax_hme_get_posts() /path/to/site/wp-includes/class-wp-hook.php:287
[27-Jun-2020 10:38:27 UTC] PHP   6. HME_MENU_EDITOR\HMEMenuEditor->hme_get_posts() /path/to/site/wp-content/plugins/wp-headless-menu-editor/includes/classes/menu_editor.class.php:198
[27-Jun-2020 10:38:27 UTC] PHP   7. get_posts() /path/to/site/wp-content/plugins/wp-headless-menu-editor/includes/classes/menu_editor.class.php:217
[27-Jun-2020 10:38:27 UTC] PHP   8. WP_Query->query() /path/to/site/wp-includes/post.php:2050
[27-Jun-2020 10:38:27 UTC] PHP   9. WP_Query->get_posts() /path/to/site/wp-includes/class-wp-query.php:3432
[27-Jun-2020 10:38:27 UTC] PHP  10. wpdb->get_results() /path/to/site/wp-includes/class-wp-query.php:3015
[27-Jun-2020 10:38:27 UTC] PHP  11. wpdb->query() /path/to/site/wp-includes/wp-db.php:2641
[27-Jun-2020 10:38:27 UTC] PHP  12. wpdb->_do_query() /path/to/site/wp-includes/wp-db.php:1912
[27-Jun-2020 10:38:27 UTC] PHP  13. mysqli_query() /path/to/site/wp-includes/wp-db.php:2024
[27-Jun-2020 10:38:37 UTC] PHP Fatal error:  Allowed memory size of 268435456 bytes exhausted (tried to allocate 303104 bytes) in /path/to/site/wp-includes/wp-db.php on line 2024

When I tried to delete the plugin, I get an undefined function:

[27-Jun-2020 10:42:55 UTC] PHP Fatal error:  Uncaught Error: Call to undefined function hme_get_posts() in /path/to/site/wp-content/plugins/wp-headless-menu-editor/uninstall.php:7
Stack trace:
#0 /path/to/site/wordpress/wp-admin/includes/plugin.php(1222): include()
#1 /path/to/site/wordpress/wp-admin/includes/plugin.php(956): uninstall_plugin('wp-headless-men...')
#2 /path/to/site/wordpress/wp-admin/includes/ajax-actions.php(4545): delete_plugins(Array)
#3 /path/to/site/wordpress/wp-includes/class-wp-hook.php(287): wp_ajax_delete_plugin('')
#4 /path/to/site/wordpress/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters('', Array)
#5 /path/to/site/wordpress/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#6 /path/to/site/wordpress/wp-admin/admin-ajax.php(175): do_action('wp_ajax_delete-...' in /path/to/site/wp-content/plugins/wp-headless-menu-editor/uninstall.php on line 7

• WordPress: 5.4.2
• PHP: 7.4.1