When you adjust the color values or alpha of a color node, the node will change size on the graph. This is fixed by closing the graph and reopening it.

1. Install Unity
2. Open the attached project
3. Open the PBRGraph.shadergraph
4. Adjust the color and alpha of the color node in the graph

Expected Result:
The color node updates to show the new color/alpha, but does not shrink or grow.

Actual Result:
When adjusting the color, the node grows in size. When adjusting the alpha, the node shrinks right down.

Tested on Windows.

Occurs on:
2019.1.0a9 with Shader Graph 5.0.0-preview
2018.3.0b11 with Shader Graph 4.1.0-preview