Unable to find where the default value of Message field (for edit) custom field is set

[Shubha Prashanth]

I have a strange issue.

I have some pop up screens during certain transitions which has certain messages for the users.

The message has been added to custom fields of type "Message field (for edit)"

The message has been appearing correctly during transitions and there is no issue there.

I would like to edit the message now but I cannot find where the message is set !!

The default value of the custom field appears empty and I cannot find where the message is set!! Please provide some pointers as to where default value for Message field can be set other than in default value. 

[Nic Brough -Adaptavist-]

Admin -> Custom fields -> Your custom message field -> Configure

[Shubha Prashanth]

Thanks Nic. 
The default value under Admin -> Custom fields -> Your custom message field -> Configure is EMPTY!!

Although, I see the message on the screen. It’s mysterious .. 

Any suggestions? 

[Nic Brough -Adaptavist-]

It's not empty.  Or you're not looking at the right thing.