Click on Edit Categories on the module's main page to display the category editing page.

To add a category, scroll down to the bottom of form. In the first empty field under ID, enter a unique internal name for your new category, such as stuff. Then, in the field next to it under Displayed description, enter the name that will appear in Webmin, such as Thirdparty.

Existing categories that you have added can be edited by changing the fields in this section, as well. You should not, however, change the entries in the ID column, as they are used internally to associate modules with categories. The ID is never visible to users anyway—only the displayed description is.

To change the name of one of the default categories displayed at the top of the form, select the second radio button next to it and enter a new description into the text box to the right. If Default is chosen, the standard name determined by the current language will be used.

Hit the Save Categories button at the bottom of the form to activate the new categories. You can now move modules into any category that you have created.

Click on the Reassign Modules icon on the main page.

The page that appears lists every installed Webmin module and the category in which it currently resides. For each module that you want to move, select a new category from the menu next to its name.

Click on the Change Categories button at the bottom of the page to move the modules.