Demand Gen campaigns in Google Ads can now integrate HTML5 ads alongside static image ads for the Google Display Network (GDN). This update enhances flexibility, making the transition from classic Display campaigns to Demand Gen more seamless.
The updated help page explains that advertisers can upload specific image and HTML5 ads to serve on GDN within Demand Gen campaigns. Advertisers can include custom static HTML5, AMPHTML, and dynamic feed-driven HTML5 assets. These formats must be uploaded as .ZIP files.

A new note specifies that while HTML5 ads are supported in Demand Gen, they serve only on the GDN, excluding channels like YouTube, Discover, Maps, and Gmail.
Read the official help page here: Uploaded display ads specifications.
This update was spotted by Hana Kobzová.