There is a new tool in the PCB editor called “Position Interactively”. It allows you to position an item by drawing a line and then redefining what that line should be.
The obvious use is a more direct way to manipulate objects than first getting it into a known position and then using Move Exact. However, it can also be used to set alignment in one axis or the other:
And the vector doesn’t have to be on either object, so it allows to directly use a dimension of something else and use it as a movement for the selection:
KiCad now supports vias with different diameters on different copper layers. This can be used for situations such as increasing annular ring size on one side of the board to use a via as a testpoint, or decreasing annular ring size on inner layers.