Hi @Anonymous
As @OliverRodrigues mentioned, try the workaround.
The way I would do it as of now is
1. Go to https://make.powerapps.com/
2. Choose the right environment
3. Dataverse > Tables > Custom > Forms > Choose main Form
4. Hit Save and publish
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In Design Studio
1. Pres sync configuration and press "Ctrl+F5."
2. Add the form component on the page of your choice
3. Choose the custom table where you built your main form
4. Now you can see all the forms in Power Pages
Hope it helps.
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