Of course, the most confidential thing is coated glass with zero transmittance-nonsense, you can't buy it in the market unless you customize it or know technical experts in this field. This kind of glass is used in my bathroom. If the two sides are folded in half, you can directly observe the solar eclipse.
It is recommended to use hollow laminated glass, and the middle layer is opaque enough to protect privacy.
The second is to install shower curtain.