I use Advanced Module Manager. Since the last update, I get the following error message when I try to save a module. The error seems to be caused by AMM, because when I uninstall AMM, the error is gone.
Joomla\CMS\Form\Field\EditorField::filter field `content` calls a deprecated filter class JComponentHelper, the class needs to be namespaced use \Joomla\CMS\Component\ComponentHelper instead or activate the backward compatible plugin.