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:
