Is there a method to target an open Finder window from the "Save" dialog? In some ancient version of the Mac OS, I seem to recall that, while in a "Save" dialog, there was a way (or an extension which provided a way) to click on an open folder in the Finder in order to specify that directory as the save target. Does that functionality still exist?

Context: I needed to save a new AppleScript (using Script Editor) into the ~/Library/Scripts directory and could not find a way to do it without manually navigating to the directory through multiple clicks. The dropdown menu in the "Save" dialog did not list the directory because I had not saved to it recently. The directory was open right next to the editor. I know about the accelerators to navigate to the top level directories but those don't help in this case.
The specific software you are probably alluding to is Default Folder X - which even allows you to click through any intervening windows to return to a folder visibly open on the Finder desktop. It also has a pre-determined list of 'useful' places &amp; a history list. I do consider it one of the indispensible utilities on Mac.

Alternatively, macOS itself allows you to drag any visible folder onto a file-picker dialog to send the dialog to that location.

Fullscreen apps may interrupt either of those efforts - but I have a particular set of reasons I absolutely never use fullscreen, so I'm not certain how it will respond.