Error v6.3.1 Classes/Admin/Tinymce_Button.php missing

An error of type E_ERROR was caused in line 15 of the file ROOT/wp-content/plugins/democracy-poll/autoload.php. Error message: Uncaught Error: Failed opening required 'ROOT/wp-content/plugins/democracy-poll/classes/Admin/Tinymce_Button.php' (include_path='.:/opt/alt/php83/usr/share/pear:/opt/alt/php83/usr/share/php:/usr/share/pear:/usr/share/php') in ROOT/wp-content/plugins/democracy-poll/autoload.php:15
Stack trace:
#0 ROOT/wp-content/plugins/democracy-poll/classes/Admin/Admin.php(25): DemocracyPoll\{closure}()
#1 ROOT/wp-content/plugins/democracy-poll/classes/Plugin_Initor.php(50): DemocracyPoll\Admin\Admin->init()
#2 ROOT/wp-content/plugins/democracy-poll/classes/Plugin_Initor.php(34): DemocracyPoll\Plugin_Initor->admin_init()
#3 ROOT/wp-content/plugins/democracy-poll/democracy.php(34): DemocracyPoll\Plugin_Initor->plugin_init()
#4 ROOT/wp-includes/class-wp-hook.php(341): DemocracyPoll\init_plugin()
#5 ROOT/wp-includes/class-wp-hook.php(365): WP_Hook->apply_filters()
#6 ROOT/wp-includes/plugin.php(522): WP_Hook->do_action()
#7 ROOT/wp-settings.php(749): do_action()
#8 ROOT/wp-config.php(103): require_once('...')
#9 ROOT/wp-load.php(50): require_once('...')
#10 ROOT/wp-admin/admin.php(35): require_once('...')
#11 ROOT/wp-admin/index.php(10): require_once('...')
#12 {main}
  thrown

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