Custom attributes may be edited in the system's Settings menu, located in the left main vertical panel. Navigate to the Custom Attributes secondary menu.
If a custom attribute has not been used in a project yet, it may be edited. To edit, click on the vertical three dot menu for the specific custom attributes and select Edit.
Click the Edit button for the desired field, and click Next to review the other details. When all the details are reviewed, the Update button will be become available. Click on Update to finalize. If the custom attribute has already been used in a project, an error message will appear that will indicate it has been used and the changes cannot be made.