Fatal error since actual Version

Fatal error: Uncaught Error:
Call to undefined function wp_get_current_user() in /mypath/wp-includes/capabilities.php:911
Stack trace:
#0 /mypath/wp-content/plugins/contexture-page-security/core/CTXPS_Security.php(112): current_user_can('edit_others_pos...') 
#1 /mypath/wp-includes/class-wp-hook.php(326): CTXPS_Security::filter_loops(Array)
#2 /mypath/wp-includes/plugin.php(256): WP_Hook->apply_filters(Array, Array)
#3 /mypath/wp-includes/class-wp-query.php(3620): apply_filters_ref_array('the_posts', Array)
#4 /mypath/wp-includes/class-wp-query.php(3949): WP_Query->get_posts()
#5 /mypath/wp-includes/query.php(99): WP_Query->query('post_type=custo...')
#6 /mypath/wp-content/plugins/custom-css-js/includes/admin-screens.php(1379): query_posts('post_type=custo...')
#7 /mypath/wp-content/plugins/custom-css-js/includes/admin-screens.php(1460): CustomCSSandJS_Admin->build_search_tree()
#8 /mypath/wp-content/plugins/custom-css-js/includes/admin-screens.php(90): CustomCSSandJS_Admin->update_custom_codes_for_block_editor()
#9 /mypath/wp-content/plugins/custom-css-js/includes/admin-screens.php(36): CustomCSSandJS_Admin->add_functions()
#10 /mypath/wp-content/plugins/custom-css-js/includes/admin-screens.php(1773): CustomCSSandJS_Admin->__construct()
#11 /mypath/wp-content/plugins/custom-css-js/custom-css-js.php(80): include_once('mypath...')
#12 /mypath/wp-content/plugins/custom-css-js/custom-css-js.php(42): CustomCSSandJS->__construct()
#13 /mypath/wp-content/plugins/custom-css-js/custom-css-js.php(317): CustomCSSandJS::instance()
#14 /mypath/wp-content/plugins/custom-css-js/custom-css-js.php(320): CustomCSSandJS()
#15 /mypath/wp-settings.php(545): include_once('mypath...')
#16 /mypath/wp-config.php(129): require_once('mypath...') 
#17 /mypath/wp-load.php(50): require_once('mypath...')
#18 /mypath/wp-admin/admin.php(35): require_once('mypath...')
#19 /mypath/wp-admin/update-core.php(10): require_once('mypath...')
#20 {main} thrown in /mypath/wp-includes/capabilities.php on line 911

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