There are several interfaces where we have the option to add a new item and rearrange existing items in the same place. On the user roles page the "Add role" button is waay off to the right, and is easily overlooked. On the field UI the "Save" button both adds a new role and saves the order.
Roles:

Fields:

Let's implement the pattern from the Field UI form on the Roles page too.
Also related: https://github.com/backdrop/backdrop-issues/issues/927
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@yorkshirepudding thank you for the additional info on improving discoverability and a handy way to keep a list of projects for reuse.
Why not add a Github star?
It is a good point @izmeez and when I was researching repo discoverability I found that GitHub search does prioritise matches with more stars. This is what I was researching for:...
Why not add a Github star?
Do you have a separate development environment and transfer database and config between sites?
Wierd happenings regarding updates...