class BlockPluginHasSettingsTrayFormAccessCheck

class BlockPluginHasSettingsTrayFormAccessCheck implements AccessInterface {
    
    /**
     * Checks access for accessing a block's 'settings_tray' form.
     *
     * @param \Drupal\block\BlockInterface $block
     *   The block whose 'settings_tray' form is being accessed.
     *
     * @return \Drupal\Core\Access\AccessResultInterface
     *   The access result.
     */
    public function access(BlockInterface $block) {
        
        /** @var \Drupal\Core\Block\BlockPluginInterface $block_plugin */
        $block_plugin = $block->getPlugin();
        return $this->accessBlockPlugin($block_plugin);
    }
    
    /**
     * Checks access for accessing a block plugin's 'settings_tray' form.
     *
     * @param \Drupal\Core\Block\BlockPluginInterface $block_plugin
     *   The block plugin whose 'settings_tray' form is being accessed.
     *
     * @return \Drupal\Core\Access\AccessResultInterface
     *   The access result.
     *
     * @see settings_tray_preprocess_block()
     */
    public function accessBlockPlugin(BlockPluginInterface $block_plugin) {
        return AccessResult::allowedIf($block_plugin instanceof PluginWithFormsInterface && $block_plugin->hasFormClass('settings_tray'));
    }

}