A couple of community contributions for custom dialogs have landed in the Pulse inbox recently. The official documentation on Dialogs and Sidebars in Google Workspace Documents is an excellent starting point, but if you prefer learning from video tutorials Chanel Greco has recently published Google Apps Script Alert – Deep Dive on the saperis YouTube channel.
If you’d like to go a little further this post from Pablo Felip details how custom dialogs can be dynamically resized using the methods in
Source: Cuadros de diálogo de tamaño dinámico en Apps Script
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