Hello,
 
We noticed that when we configure the formulasGroupName value to "/", specifically:
global: {
  localization: {
    fieldsList: {
      formulasGroupName: "/"
    }
  }
}
We would always get a TypeError: d is null in the console when trying to create/add a Calculated Value from the Fields popup. Attached is a jsFiddle for convenience. There is no immediate need for us to have this fixed, but we thought we would bring attention to this in case others are running into the same problem.
 
Please let us know if you need any additional information or if the link is broken.
 
Kind regards,
Henry
Hello, Henry, 
 
Thank you for reporting this to us.
We have added it to our backlog, and we will notify you as soon as it is fixed.
 
By the way, you can add calculated values in the root of the Field List by setting formulaGroupName to an empty string:
global: {
  localization: {
     fieldsList: {
        formulasGroupName: ""
     }
  }
},
Here is a JSFiddle example for illustration.
 
Please let us know if this helps.
 
Kind regards,
Vera
Hello, Vera,
 
That's good to know, thanks much!
 
Kind regards,
Henry
Hello, Henry,
 
We are glad to announce that the issue with / in the formulasGroupName was fixed.
 
This is provided in the 2.9.2 version of Flexmonster: https://www.flexmonster.com/release-notes/.
 
You are welcome to update the component. Here is our updating to the latest version tutorial for guidance: https://www.flexmonster.com/doc/updating-to-the-latest-version/.
 
Please let us know if the fix works fine for you.
 
Kind regards,
Vera
Hello, Vera,
 
Upgrading to 2.9.2 looks to have fixed the issue, thanks much to you and the team!
 
Kind regards,
Henry