Fatal error: Uncaught Error: Attempt to modify property “checked” on null

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Fatal error: Uncaught Error: Attempt to modify property "checked" on null
in /htdocs/wp-content/plugins/the-seo-framework-extension-manager/bootstrap/update.php on line 298

Call stack:

TSF_Extension_Manager_push_update()
wp-includes/class-wp-hook.php:324
WP_Hook::apply_filters()
wp-includes/plugin.php:205
apply_filters()
wp-includes/option.php:2368
set_site_transient()
wp-includes/update.php:393
wp_update_plugins()
wp-includes/update.php:1022
_maybe_update_plugins()
wp-includes/class-wp-hook.php:324
WP_Hook::apply_filters()
wp-includes/class-wp-hook.php:348
WP_Hook::do_action()
wp-includes/plugin.php:517
do_action()
wp-admin/admin.php:175
require_once()
wp-admin/index.php:10