I have a Mac Mini late 2012 running MacOS Catalina (10.15.4). I have a weird issue with drag and drop in Finder. When I drag a file/folder into a new folder to move it there, it does not let me hold down the mouse and navigate through the subfolders. I can drag and drop "one folder deep", but Finder does not open the folder that I drag on top of.
For example:
In this case, I could drag the "Database" folder into the "System Admin" folder" (Whoops that name lol) but not into the "Linux" subfolder inside "System Admin". Finder will only let me drag "Database" one folder deep. It will not open the "System Admin" folder and show me the subfolders where I could then drag on into "Linux".
I'm not exactly sure long this has been like this, since I usually use other methods than drag and drop to get stuff done, but I think that it has been like this since I upgraded from High Sierra to Mojave.
I am using the Magic Mouse 2 if that helps. I have been using is ever since I got this mac though, back when drag and drop still worked fully. And if I use other mice the problem is still there.
Any help is welcome!
Best Answer
So what worked for me was to turn on Spring-loading delay in System Preferences > Accessibility > Pointer Control.
I have no idea why it would not work without this, but it works fine now. Well, almost fine. I still do not get the little green plus sign when dragging files to a new location, but I am able to drag through into subfolders.