Random level selection for browser-based game challenges

I’ve been experimenting with Firefox add-ons for gaming-related workflows and recently built a small extension that randomly selects levels for challenge runs. The idea is pretty simple: instead of manually choosing a level, the extension can help pick one at random and make challenge sessions a little less repetitive. I’m curious how other developers approach small gaming utilities for Firefox. Do you usually keep these tools focused on one feature, or add things like history, filters, or custom difficulty settings?
I made a small add-on as an experiment: Firefox add-on
Id be interested in feedback from other add-on developers, especially on features that would make this type of extension more useful.