(Resolved) Bent Normals bug in shader graph?

Unity Engine
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Hey, I cannot figure out how to use bent normal maps in shader graph (Using HDRP 10.7 and latest 2020.3 LTS). No matter what I try, I end up with seams and lighting in general looking incorrect.

The following images show the issue, first the lighting produced by Lit Shader, which seems correct:

7572256--937801--Capture-lit-shader.PNG.jpg
7572256--937801--Capture-lit-shader.PNG.jpg1086×880 128 KB

Here is same with a Shader Graph based shader, using same texture for bent normal:

7572256--937807--Capture-shader-graph.PNG.jpg
7572256--937807--Capture-shader-graph.PNG.jpg1087×871 125 KB

There are clearly visible seams, and some of the lighting seems to be off.

This is the config for bent normal texture in Shader Graph:

7572256--937810--shader-graph.PNG
7572256--937810--shader-graph.PNG718×244 19.8 KB

I guess it’s a bug in shader graph? Or do I need to do something else to use a bent normal map?

2

Update: by try and error, I found that this seems to be related to wrong tangent information in the Vertex stage, so probably not a bug, but wrong usage of shader graph.