Thank you @Krzysztof.N ,
Of course. I have created this repro for you: Dropbox - Translucency glass test.rar - Simplify your life
It seems to be related with “two sided” glasses.
I have also noticed something strange with the global lighting, but wasn’t able to repro it again (it happened me twice, with that scene, just after fixing the exposure values, so maybe it’s related to exposure): sometimes, after reopening the project and/or (not sure) the map, or duplicating the scene, the global illumination was quite more darker, if you can try some random reopening or duplicating.
Best regards