System Information
Operating system:
Graphics card:

Blender Version
Broken: (example: 2.80, edbf15d3c044, master, 2018-11-28, as found on the splash screen)
Worked: (newest version of Blender that worked as expected)

Short description of error
The tweak gizmo of the node editor used to drag nodes by a single click-drag. That conveniant behavior is gone. Now you not only have to click twice befor being able to drag the node, but you have to let passing some time inbetween the actions. That's a serious regression to the previous workflow.

Exact steps for others to reproduce the error
Open the file.
Set the gizmo to tweak if you haven't already. No reason to use anything else btw.
Try to drag a node. It used to work by only hovering over the node and then click-hold and drag.