Unique ID widget: Ability to generate the unique ID based on a condition set on the form

Is there a way to make the unique ID widget only generate the next sequential number only if a certain condition is met?

I have it set up, but I only want it to work if a certain field is marked "approved."

Unfortunately, no. The widget increments every time the form is submitted. It cannot be used with conditions as well.

We don't have any other widget that can achieve the requirement you mentioned, but let me forward this as a feature request. Though I cannot provide you an ETA when or will it be implemented, we'll let you know here for updates.