Shader nodes display an error message in the latest 2021.4.12 previews. When double-clicking, the node browser then shows two empty choices but when clicking them, nothing happens.
The patch is very big and has circular references with other documents, however, the error didn’t exist in earlier previews.
EDIT: This error isn’t present in 1356, the build right before.
Any chance we can reproduce this on our side? The hint that it wasn’t present in the build one before does not really help much, because the changes don’t touch that topic at all.
I’ve just tried this in 1365 and it didn’t happen there either. It was probably just a glitch. If it happens again I’ll try to reproduce it consistently.