function setEditorTheme({ caption, theme }) {
		editorManager.editor.setTheme(theme); // main editor
		editor.setTheme(theme); // preview
		appSettings.update(
			{
				editorTheme: theme,
			},
			false,
		);
		updateCheckedItem(caption);
	}
Sets the selected editor theme
@param {object} param0
@param {string} param0.theme