WordPress Error: Uncaught Error: Undefined constant “PPS_SITE_URL”

Dear Supsystic Team,

since the last version of the popup plugin I get only a WordPress Critical Error when the plugin is activated.

Disabling other plugins did not bring success. Only with deactivated popup plugin the page is accessible again.

After deactivating the popup plugin the error disappeared, however then the Popup Pro plugin caused another error. After deleting the Popup Pro plugin, the page works again.

Is there an update for this plugin to solve the problem?

We are running our site under current WordPress as well as PHP 8.0.

Best thanks and greetings

WordPress-Version 6.0
Aktives Theme: Avada (Version 7.7.1)
Aktuelles Plugin: Popup by Supsystic (Version 1.10.14)
PHP-Version 8.0.20

Error-Details
==============
Ein Fehler vom Typ E_ERROR wurde in der Zeile 126 der Datei /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/modules/popup/models/popup.php verursacht. Fehlermeldung: Uncaught TypeError: Cannot access offset of type string on string in /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/modules/popup/models/popup.php:126
Stack trace:
#0 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/classes/model.php(113): popupModelPps->_afterGetFromTbl()
#1 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/classes/model.php(192): modelPps->getFromTbl()
#2 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/modules/popup/models/popup.php(438): modelPps->getById()
#3 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/modules/popup/views/popup.php(61): popupModelPps->getById()
#4 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/modules/popup/mod.php(49): popupViewPps->getEditTabContent()
#5 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/modules/options/views/options.php(30): popupPps->getEditTabContent()
#6 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/popup-by-supsystic/modules/options/mod.php(40): optionsViewPps->getAdminPage()
#7 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/class-wp-hook.php(307): optionsPps->getAdminPage()
#8 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters()
#9 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/plugin.php(476): WP_Hook->do_action()
#10 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-admin/admin.php(259): do_action()
#11 {main}
thrown`

WordPress-Version 6.0
Aktives Theme: Avada (Version 7.7.1)
Aktuelles Plugin: PopUp by Supsystic PRO (Version 1.9.73)
PHP-Version 8.0.20

Error-Details
==============
Ein Fehler vom Typ E_ERROR wurde in der Zeile 87 der Datei /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/____popup-by-supsystic-pro/wpUpdater.php verursacht. Fehlermeldung: Uncaught Error: Undefined constant “PPS_SITE_URL” in /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/____popup-by-supsystic-pro/wpUpdater.php:87
Stack trace:
#0 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/____popup-by-supsystic-pro/wpUpdater.php(40): wpUpdaterPps->prepareRequest()
#1 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-content/plugins/____popup-by-supsystic-pro/popup-by-supsystic-pro.php(40): wpUpdaterPps->checkForPluginUpdate()
#2 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/class-wp-hook.php(309): checkForPluginUpdatepopupBySupsysticPro()
#3 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/plugin.php(191): WP_Hook->apply_filters()
#4 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/option.php(1992): apply_filters()
#5 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/update.php(354): set_site_transient()
#6 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/update.php(896): wp_update_plugins()
#7 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/class-wp-hook.php(307): _maybe_update_plugins()
#8 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters()
#9 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-includes/plugin.php(476): WP_Hook->do_action()
#10 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-admin/admin.php(175): do_action()
#11 /mnt/web320/c0/22/59175022/htdocs/WordPress_SecureMode_02/wp-admin/index.php(10): require_once(‘…’)
#12 {main}
thrown`

The page I need help with: [log in to see the link]