Some advertisers have the option of joining a test to use AI generation to expand videos.
Here’s how to find it and what you need to know…
Where to Find It
Go to Advertising Settings.

Click the box for Advantage+ Creative.

Some people have a section for Test New AI Generation Features.

It reads:
If you’re currently using all Advantage+ creative enhancements, you can test new AI features and use innovative creative improvements before other advertisers. Choose the features you would like to test below and we may deliver them on fewer than 5% of your impressions across all eligible campaigns associated with this ad account.
I’ve covered the Text Extraction Optimization option before. Now there’s Expanded Video as well.
How it Works
Click Edit Tests.

Here’s how Meta defines this feature:
We will use AI to extend your video’s aspect ratio so it will look more natural on certain placements.
The example Meta provides is of a landscape video that is expanded to fit 9 x 16. The water and sky in the scene are AI generated.
Results
You won’t know how this enhancement impacts results or how often it’s used, but that’s always the case with Advantage+ Creative. If you’re going to turn this on, there needs to be a certain level of trust that you’re okay with whatever happens.
As noted earlier, of course, “Test AI Generated Features” will apply to fewer than 5% of your impressions.