How does the ComboBox in the UE5 control behave like UE4, with a transparent background?
UE4:
UE5:
Hey there @goodriver! All you have to do is go to the button style, choose the styles you want to hide and then change their Draw As type to None and it will not draw them.
Hello, your approach is hidden. What I want is an alpha background
Thank you for your reply. What I need is Alpha in the options.

Ahhhhh I see where the issue is. It doesn’t look like the style for the background are exposed outside of slate based on a post from a while back.
It doesn’t look like that’s changed since then. It looks like the recommendation most people use is to create a new widget type for them.
Have this bugs been fixed?
No, I’m still stuck on this issue.
Update
Edit the menu border brush under ‘style’ and set ‘draw as’ to none. This gives you a completely transparent dropdown box menu background. I didn’t realise the background was a thick border line. It looked filled in so I was looking eveywhere for ‘background’ colour.
While this solution seems to work in older versions (I’ve seen a video of a person using these steps to get rid of the grey background in 5.4) , in 5.6 this yields no result - the background of the menu is still gray. Any Item styling AS WELL as custom styles for menu borders goes on top of that. Several comments on that video from people using 5.6 confirmed this unfortunate truth.
P.S. Here’s the 5.4 video: https://youtu.be/nc8js3LJ6wE?si=Ei5W8GdSsDus-uU7