So I am trying to make a glassy transparent cup according to a tutorial but I seem to have misclicked something and now every default material when I change the viewport into preview material is the default forest one that comes with BLENDER 2.90. However, when I render the object with the camera it shows the way I want it.
I have tried removing the material from the cup or the liquid and adding a new one with the default white color. when I turn the Transparency to 1 and Roughness to 0 it becomes the forest HDRI again.
blend file: https://pasteall.org/blend/154d7b8156aa42bbb0c41dcb332a32ab