PHP Error with Roundcube through Hestia

Hello,
I have been struggling to get the webmail part of my server to work. I do have a working Nextcloud server. But regarding the webmail part of the server, I keep getting the 500 error that says

Oops… something went wrong!
An internal error has occurred. Your request cannot be processed at this time.
For administrators: Please check the application and/or server error logs for more information.

Checking /var/log/roundcube/errors.log I see the following:

[15-Nov-2022 11:03:26 America/New_York] PHP Warning:  Uninitialized string offset 0 in /var/lib/roundcube/program/lib/Roundcube/rcube_utils.php on line 1308
[15-Nov-2022 11:12:09 America/New_York] PHP Warning:  Uninitialized string offset 0 in /var/lib/roundcube/program/lib/Roundcube/rcube_utils.php on line 1308

Looking at line 1308 on the “rcube_utils.php” file, I see the following block of code

            if ($arg[0] == '-') {
                $key = preg_replace('/^-+/', '', $arg);
                $sp  = strpos($arg, '=');

How do I fix this error?

My server uses the Oracle Free Tier services, ARM processors, Ubuntu Server 22.04 LTS, Hestia 1.6.11

I have no idea

Maybe create an issue at