Unhandled error when upgrading to 21.1.7

[karlson2k]

Got error message in the upgrade log in the GUI:

[25/28] Extracting os-tor-1.8_2: .......... done
Stopping configd...done
Starting configd.
Keep version OPNsense\Tor\ACLSocksPolicy (0.0.0)
Keep version OPNsense\Tor\General (1.0.0)

Fatal error: Uncaught Error: Class 'Phalcon\Validation\Message\Group' not found in /usr/local/opnsense/mvc/app/models/OPNsense/Base/BaseModel.php:442
Stack trace:
#0 /usr/local/opnsense/mvc/app/models/OPNsense/Base/BaseModel.php(564): OPNsense\Base\BaseModel->performValidation(false)
#1 /usr/local/opnsense/mvc/app/models/OPNsense/Base/BaseModel.php(686): OPNsense\Base\BaseModel->serializeToConfig()
#2 /usr/local/opnsense/mvc/script/run_migrations.php(55): OPNsense\Base\BaseModel->runMigrations()
#3 {main}
  thrown in /usr/local/opnsense/mvc/app/models/OPNsense/Base/BaseModel.php on line 442
Reloading plugin configuration
Configuring system logging...done.
Reloading template OPNsense/Tor: OK
[26/28] Reinstalling os-theme-rebellion-1.8.7...

The upgrade process finished fine, but I'm not sure whether all settings are successfully migrated.

[karlson2k]

Similar problem is reported here: https://forum.opnsense.org/index.php?topic=23581.0