How to use the default Godot 3.0 theme in project?

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:bust_in_silhouette: Asked By chanon

I have a custom ‘addon’ that implements a custom resource editor. I am porting it to Godot 3.0 however, while editing it in the design (2D) view it is using the old Godot 2.0 theme which is different from how it actually eventually shows up in the editor (which uses the new Godot 3.0 theme) and is causing a bit of a headache aligning things up correctly.

So how do I set it so that it uses the new Godot 3.0 theme while editing it?

I have seen:
https://forum.godotengine.org/16166/using-godot-3-0-theme-in-project?show=16166#q16166

But the answer there points to two very long Github discussions which having skimmed don’t seem to answer the question.

How can I use the Godot 3.0 default theme while editing my editor ‘addon’ so that I can get a WYSIWYG view of it?

:bust_in_silhouette: Reply From: Calinou

To create a project theme based on the current editor theme, create or edit a Theme resource then click Edit theme…Create From Current Editor Theme in the theme editor panel. It will be based on the current editor theme properties such as background color and contrast rate.