There are two major bugs in 2020.4. I know one is already known, but I feel like it's big enough people should know about it - the Data Profiler is currently sampling data and only displaying up to 1MB of the data stream, without notification (it says it's showing all records).
The other I haven't seen reported and is new for 2020.4: You can't drag and drop data files into Designer any more.
If you:
1. Open a File Explorer Window
2. Try to drag and drop a file onto the Designer to add it as a data input tool
OR
1. drag a data input onto the canvas
2. click on the arrow for "connect a file or database"
3. try to drag a file into the area that says "drag and drop a file here"
Then NOTHING happens. You can't do it anymore. You just get the "NO" icon on your mouse. Any idea when this will be fixed? I'm going to have to revert back to 2020.3.
I seem to have no problem drag/drop files onto a canvas. Can you check that you're not running Alteryx with Admin Privileges? File Explorer can never run with Admin Privileges and you can't drag drop from a non-admin program to an admin program.
I still can do both after upgrade.
I can drag & drop also... I suggest you to check what @KaneG suggested in previous comment.
Regards!