You can display your site widget in the following areas:
Note: Essential widgets are automatically added to a site when an app is installed and can only appear once, so they don't appear in the Add Elements panel or the Manage Apps page.
When creating your site widget, configure the following content:
Learn more about creating a custom element site widget:
Your widget appears in the panel's App Widgets section. Wix users can find it there and add it to any page on a site.
The following image shows how a widget appears in the panel:

Your widget appears in the Manage Apps page of the site dashboard. Wix users can find it listed under your app and add it to any page on a site.
The following image shows how a widget appears in the Manage Apps page:

The preview image you provide appears in both the Add Elements panel and the Manage Apps page. When creating your preview image, keep the following content and technical guidelines in mind.