Force Finder to use only a single window?
I figured it out. Oddly, the Finder setting "Open folders in tabs instead of new windows" seems to do nothing unless the following setting is also in effect: Settings > Dock > Prefer tabs when opening documents set to Always.
Now commands to open folders, whether from Spotlight or "Reveal in Finder" open in new tabs instead of windows.
That can be done
Go to Finder Preferences and set it like this..
Open Folders in Tabs ...
If you still want to see more Finder windows (Tabs) click on the + on the right and it will open new Tab in same window.
