Joomla 4
JCE 2.9.17

Trying to create a new editor profile ( JCE Editor Pro --> Profiles --> New ) throws the error message "filter_var_array(): Argument #1 ($array) must be of type array, null given" after clicking any of the "Save" buttons.

It works fine in Joomla 3

I installed a fresh Joomla 4 online, to which I made no modifications and to which I installed only the JCE Pro 2.9.17
The problem prevails.

I've just sent you administrator login information to check it out.

Thank you Ryan; the new Beta seems to be working fine on the online installation.

I installed it on my local server (Windows 10) and unfortunately It now displays a new error message.
Trying to save a new profile I get the error message "Save failed with the following error: Field 'checked_out_time' doesn't have a default value"

The MariaDB version on my local server is 10.5 and on my online server is 10.2, but the Joomla and the PHP versions are the same on both servers.

I'll be damned!

It's neither the type of computer/operating system, nor the Joomla/PHP/SQL at fault.
I tried today on my local server on a new Joomla 4 with only the JCE (2.9.18beta) installed, and had no problem in creating a new profile.

The other Joomla 4 installation still exhibits the error message I mentioned in my previous post,. This installation is an upgrade from Joomla 3 to Joomla 4 with all extensions involved upgraded to their Joomla 4 versions.
I gradually uninstalled all no Joomla extensions. Neither the uninstallation of all other extensions, nor the uninstallation of the JCE and its installation again solved the problem.

I can't be sure if the problem is due to a leftover code from the other extensions or from the upgrade from Joomla 3 to Joomla 4. More tests are needed.

Excellent!
That worked great, on upgraded Joomla 3 --> Joomla 4 site.

Thank you Ryan.