Editor compatibility
Wix Blocks apps aren't supported in the Wix Harmony editor. Existing Blocks apps remain available for purchase on the Wix App Market for Wix Editor and Wix Studio sites. To learn more, see About Wix Harmony and Blocks.
The Configuration tab in the Editor Experience panel enables you to determine the way your widget and its elements look and behave in the editor when they're installed on a site.
When a site builder installs your widget on a site and opens the editor, the widget and its elements have floating action bars, just like any other Wix site element. For example, this is the action bar of the widget's button, which allows the site builder to perform various actions on the button:

Blocks lets you modify these action bars. You can add, remove or reorder buttons. You can determine which panel opens when a button is clicked, and more. The modification options vary, depending on whether you select a widget, or one of its elements, and which element you select.
By modifying the action bars you can give site builders more options for customizing your app when they install it on their site. You can also decide that you want to limit what they can change in your widget.
UX guidelines Read our UX guidelines for clear and effective action bars
To modify action bars:
panel.Now, you can modify action bars in two ways:

icon to expand it). 

icon to expand it).

Notes
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