Operating system: Windows-10 64 Bits
Graphics card: GeForce GTX 1070 NVIDIA 442.19
Broken: version: 2.83 (sub 6), branch: master, commit date: 2020-03-06 22:46, hash: rBdcdcc2348842
Short description of error
Filled cap of curve together with weld + bevel modifier doesn't have smooth shading.
Exact steps for others to reproduce the error
Launch below blend file and observe the non-smooth shading at the cap.
1- Launch default Blender.
2- Create a bezier and a circle curves.
3- Use circle as bevel object in bezier curve and enable fill caps option.
4- Create weld and bevel modifier for bezier curve object.
5- Disable clamp overlay, set limit method to angle and increase segment to 5, set offset 0.02m in bevel modifier.
6- Observe the non-smooth shading at the cap of the bezier curve.