As shown here: https://youtu.be/E_nkIP2TR_g?t=694
Also, it is no longer possible to make things very dark grey or black. I made a Dark Theme preferences file here: https://currentsound.com/general/cubase-10-dark-mode-theme/ Which still ranks high on Google for Cubase 10 Dark Theme. It’s no longer possible to make Cubase look dark like this. You can only do a light-ish grey type of color. If you download the file linked in the article in 10.5 which is here https://yadi.sk/d/Luyy5X1uWyqVPw and load it into 10.5 Cubase it will cause the transparency issue as that is the exact file I am loading in the video. Even after loading it, setting to default as shown in the video did not work. I had to manually replace every single color and save a new preferences preset.