Editor: Popup stylebox is not transparent.

[pegasusearl]

Godot version

v4.0.beta10.official [d0398f6]

System information

Manjaro Linux x86_64, Vulkan, NVIDIA GeForce GTX 1650

Issue description

Hello, I'm not sure if it's bug or not. Maybe it's supposed to work this way now that we have multi-window?

In Godot 4, when using custom theme utilizing transparency on Popups derivative object, it's not rendered transparent.

While in Godot 3, it rendered properly.

Steps to reproduce

Assign Custom Editor Theme that uses transparency on Popup derivative items such as PopupMenu or TooltipPanel.

• Open the minimal reproduction project.
• Go to Editor > Editor Settings > Interface/Theme
• Then assign Custom Theme to theme.tres inside the attached minimal reproduction project.

Test by opening MenuBar and by trying to show Tooltips in the editor.

output.mp4

Menubar is using StyleBoxFlat, using shadows. The shadow is rendered without transparency and it's cropped to only shows the panel. Outside rounded corner is not transparent as well.

Tooltips is using StyleBoxTexture, everything is rendered without being cropped but no transparency.

Minimal reproduction project

MinimalUiReproduction.zip

[KoBeWi]

You need to enable transparent property in Popup.

[pegasusearl]

You need to enable transparent property in Popup.

Ah good to know.
hmm but it looks like it's for runtime only since it's in the Node's property rather than the theme/stylebox, I can't find a way to do it for editor.

[KoBeWi]

[Calinou]

This requires transparent windows to be rendered correctly in Godot 4, unless Single Window Mode is enabled in the editor settings. (This is not required for running projects as the Embed Subwindows project setting is enabled by default.)

[iacore]

Maybe this is related to #70814

[Kubulambula]

For anyone encountering this issue:
Enabling transparent_bg in addition with enabling transparent solved this issue for me

[Calinou]

Closing in favor of #76071, as this is due to the same issue.