In a situation with many jobs (where the list of unstable jobs is particularly handy) there are often a few disabled jobs as well.

The current 'Unstable jobs' widget handles disabled jobs like any other. Disabled jobs are thus included in the list if their last build failed or was unstable.

At this moment, the user can already choose to include or exclude the (non-failed) unstable jobs, using a simple checkbox.

A similar checkbox should be added to let the user include or exclude (failed/unstable) disabled jobs.