PHP warning when editing registration form

I don’t know if this is Event-Genius-related, but when I edit the registration form in the backend with WP_DEBUG switched on, I get seven PHP warnings “Array to string conversion in […]/wp-includes/class-wp-editor.php on line 851” at the bottom of the page (as soon as I switch to the ‘Registration Form’ tab).
It doesn’t seem to impede the function, editing works fine. I just wanted to tell you because it struck my eye.

## Site/Server Info ##
WordPress Version: 7.0.1
PHP Version:       8.4.16-nmm1
Server Software:   Apache
MySQL Version:     10.11.14
Active Theme:      Alnus
Site URL:          https://alnus.pro-waldstadt.de
Multisite:         No

## Active Plugins ##
Antispam Bee:                                                                    2.11.12
Enable Media Replace:                                                            4.2.2
Event Genius:                                                                    1.15
FileBird Lite:                                                                   6.5.5
Image Widget:                                                                    4.4.12
Lightbox mit PhotoSwipe:                                                         5.8.6
Loco Translate:                                                                  2.8.5
No Gutenberg - Disable Blocks Editor and Global Styles - Back to Classic Editor: 2.1.2
Regenerate Thumbnails Advanced:                                                  2.5.0
Resize Image After Upload:                                                       1.8.6
YYDevelopment - Show Pages ID:                                                   1.5.6
WordPress Importer:                                                              0.9.5

## Event Information ##
Next Event:          No upcoming events scheduled
Total Events:        2
Total Registrations: 0

## Settings ##
preserve_data:                       enabled
start_of_the_week:                   monday
full_date_format:                    custom
full_date_format_custom:             l, j. F Y
date_summary_format:                 custom
date_summary_format_custom:          d.m.Y
registration_timeline_format:        custom
registration_timeline_format_custom: d.m.Y, H:i
time_format:                         H:i
time_format_custom:                  ga
cpt_slugs: Array
(
    [event_slug] => termin
    [event_archive_slug] => events
    [venue_slug] => ort
    [venue_archive_slug] => venues
    [organizer_slug] => organizer
    [organizer_archive_slug] => organizers
    [event_category_slug] => event-category
    [event_tag_slug] => event-tag
)

email_from_address_custom:           disabled
email_from_address:                  Valid email address | Domain does not match site domain
google_maps_api_key:                 Malus31.12.
event_template:                      custom
show_export_options:                 enabled
single_event_elements: Array
(
    [0] => title
    [1] => featured_image
    [2] => date
    [3] => locations
    [4] => map
    [5] => about_details
    [6] => organizers
    [7] => categories
    [8] => tags
    [9] => capacity
)

color_theme:                         light
currency_symbol:                     $
cost_display:                        {symbol}{amount}
enable_dynamic_content_refresh:      enabled
dynamic_content_staleness_threshold: 3
show_events_in_main_loop:            disabled
default_calendar_settings:           {"view":"month","num":12,"events_per_day":3,"filter_relationship":"AND","show_toolbar":"disabled","show_pagination":"disabled","filter_bar_options":{"search":true,"venue":true,"category":false,"tag":false,"time_filter":true,"list_sort":false,"display":true},"filters":[],"color":"#7a944d","default_time_filter":"upcoming","default_list_sort_order":""}

## Debug Log ##
Log Entries: No log entries found.

## Cron Events ##
evge_cleanup_orphaned_records: 
    Next Run:                      2026-07-11 19:31:11
    Hours Until:                   11.6 hours
    Schedule:                      twicedaily