~ Changed: Update Joomla max version to 5.3 (next version, iCagenda tested on alpha release).
# [LOW] Fixed: The option to show/hide the language field in the Submit an Event form was not effective.
# [LOW][J4/J5] Fixed: Namespace Uri if site_itemid in admin events list view.
# [LOW][J4/J5] Fixed: PHP deprecated method in RSS feed view.

Changed files in 3.9.8
~ script.icagenda.php
~ com_icagenda/admin/tmpl/events/default.php
~ com_icagenda/site/models/submit.php
~ com_icagenda/site/src/Model/SubmitModel.php
~ com_icagenda/site/src/View/Events/FeedView.php