Usermin: Edit Categories not working

Information:

Virtualmin: 5.07
Webmin: 1.831
Usermin: 1.701
Theme: Authentic 18.40
OS: Ubuntu Linux 16.04.2, Linux 4.4.0-62-generic on x86_64, Intel(R) Xeon(R) CPU E3-1245 V2 @ 3.40GHz, 8 cores, 32GB DDR3 ECC

How to reproduce:

1. Usermin > Edit Categories
2. Change "login" to custom and enter: "profile"
3. press "save categories"

Result: "Failed to save categories : Missing description for servers" Where the category in bold above is random every time i repeat the 3 steps.

Expected Result: Customized category is saved.

Thanks in advance