Does transparency work in eevee I have been trying to create a transparent lens using the eevee rendering engine in 2.8 but the transparency slider has no effect. Has this feature not been implemented yet? I've looked all over the Web for an answer with no luck. I'm a noobee so am probably doing something wrong.
Use these settings:

Render → Screen Space Reflections - On
Render → Screen Space Reflections → Refraction - On
Material → Surface → Principled BSDF → Transmission - $1.000$
Material → Surface → Principled BSDF → Roughness - Adjust to your needs
Material → Settings → Blend Mode - Opaque
Material → Settings → Screen Space Refraction - ON
Material → Settings → Refraction Depth - Adjust to your needs, I generally suggest $0.8$ but depends on the thickness of the object.

Result:

(It's quite similar to Albert's answer but different)