When making a fieldset visible with Webform conditionals: The "civicrm_contact" plugin does not exist.

To simulate this error:

Create a webform with two contacts:
Contact 1 (Person)

• ask first and last name as civicrm fields
• Create a radios field: has organisation yes/no

Contact 2 (Organisation)

• Use fields Existing contact and Organisation name and make them required
• Set conditions on the fieldset: show visible when "has organisation" is yes

Saving when "has organisation" is yes (so all fields visible):
Drupal\Component\Plugin\Exception\PluginNotFoundException: The "civicrm_contact" plugin does not exist. Valid plugin IDs for Drupal\Core\Render\ElementInfoManager are: address_zone_territory, address, address_zone, address_country, commerce_entity_select, commerce_plugin_configuration, commerce_conditions, commerce_profile_select, commerce_number, commerce_price, commerce_product_rendered_attribute, contextual_links_placeholder, contextual_links, devel_table_filter, feeds_uri, field_group_accordion_item, horizontal_tabs, field_group_html_element, field_group_accordion, field_ui_table, managed_file, processed_text, text_format, geofield_latlon, geofield_dms, geofield_bounds, inline_entity_form, language_configuration, linkit, physical_number, physical_measurement, physical_dimensions, responsive_image, select_or_other_select, select_or_other_buttons, status_report_page, token_tree_table, toolbar, toolbar_item, video_embed_iframe, webform_actions, webform_computed_token, webform_message, webform_address, webform_link, webform_table_row, webform_entity_radios, webform_telephone, webform_element_states, webform_checkbox_value, webform_element_composite, webform_email_confirm, webform_likert, webform_entity_checkboxes, webform_radios_other, webform_submission_views, webform_scale, webform_time, webform_submission_navigation, webform_wizard_page, webform_variant, webform_autocomplete, webform_excluded_columns, webform_options, webform_submission_information, webform_more, webform_computed_twig, webform_help, webform_element_attributes, webform_excluded_elements, webform_term_select, webform_tableselect_sort, webform_height, webform_signature, webform_markup, webform_permissions, webform_users, webform_term_checkboxes, webform_horizontal_rule, webform_audio_file, webform_roles, webform_same, webform_html_editor, webform_image_file, webform_name, webform_mapping, webform_submission_views_replace, webform_location_places, webform_select_other, webform_image_resolution, webform_section, webform, webform_custom_composite, webform_email_multiple, webform_table, webform_codemirror, webform_terms_of_service, webform_entity_select, webform_element_multiple, webform_element_options, webform_video_file, webform_multiple, webform_rating, webform_document_file, webform_checkboxes_other, webform_table_sort, webform_contact, webform_flexbox, civicrm_select, civicrm_select_options, view, paragraphs_actions, paragraph_operations, break_lock_link, entity_autocomplete, html_tag, number, inline_template, container, details, search, tableselect, radios, status_report, textarea, vertical_tabs, item, password, language_select, html, url, form, actions, checkboxes, machine_name, pager, date, table, dropbutton, select, operations, more_link, value, token, status_messages, fieldgroup, checkbox, path, image_button, hidden, tel, file, submit, password_confirm, label, range, color, textfield, system_compact_link, button, ajax, page, link, radio, fieldset, page_title, weight, email, datetime, datelist in Drupal\Core\Plugin\DefaultPluginManager->doGetDefinition() (regel 53 van /home/vsf78xx/public_html/core/lib/Drupal/Component/Plugin/Discovery/DiscoveryTrait.php).

The error does not happen if:

• Existing organisation is NOT required
• Existing organisation is required, but the condition is not set (so field always visible)