Indeed, AppBuilder doesn't have an extension for VS Code. However, you can use the AppBuilder extension for Visual Studio with Visual Studio Community Edition
, which is free for individuals. Also, you can use the AppBuilder tools with Sublime Text by installing the AppBuilder Package for Sublime Text
Alternatively, you can do your development in VS Code and perform the AppBuilder-related tasks using the AppBuilder CLI
Also, you could log a feature request for a VS Code extension in the Ideas an Feedback portal
and post a link here, so others can vote for it.
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