I just tried it and it worked for me in the condition you described.
When you expand the action via the little arrow to the left of the action name, does it look exactly like this, including the little checkmarks and dialog boxes to the left?
If not, you'll probably want to reload the actions. From Adobe Help:
Restore actions to the default set
- Choose Reset Actions from the Actions panel menu.
- Click OK to replace the current actions in the Actions panel with the default set, or click Append to add the set of default actions to the current actions in the Actions panel.
Hope this helps.
Yes, it looks exactly like that.
I don't think it's a problem with the action -- it's a problem with the selection going away when I start the action. The selection disappears so, of course, the command feather is not available because there is nothing to feather.
Addendum: Not really expecting anything, I reset the actions as you advised and that seems to have worked. The vignette action works now. That was REALLY weird behavior from PS - I've never seen a selection just go away like that.
Thank you, Noel.