Since I upgraded to H12.1.98 I've noticed that some of the materials in the gallery seem to behave strangely. When you drag the material from the tree view into your SHOP context, Houdini thinks about for a moment, then the material icon shows up. When you click on it, all the tabs are there in the UI, but the parameters are all missing! Some of the other materials are exhibit this behavior, but some, like clay, the glow shader, some others, work fine.
If I go the SHOP context and hit the TAB key, pick the “Material Shader Builder” node, and click on it, it's all OK.

Any ideas what might be causing this? Previous versions of Houdini 12 didn't act this way.