<?xml version="1.0" encoding="UTF-8"?> <form addfieldprefix="Joomla\CMS\Installation\Form\Field" addruleprefix="Joomla\CMS\Installation\Form\Rule"> <fieldset name="site"> <field name="language" type="installation.language" label="INSTL_SELECT_LANGUAGE_TITLE" class="form-select required ms-2" default="en-GB" /> </fieldset> </form>