It looks like Google covertly used a Galaxy Z Fold 2 to fine-tune the Pixel Fold software

Google used a Samsung Galaxy Z Fold 2 to test the software for its Pixel Fold. The internal prototype, codenamed “Jumbojack,” was used to fine-tune the Pixel Fold software experience before testing on Google’s own foldable prototype. Images of Jumbojack show it running an early version of Android 12L with Google apps like Recorder and Safety. The settings menu also shows the codename Jumbojack. The test phone appears to simulate larger bezels than the Galaxy Z Fold 2, possibly to emulate the Pixel Fold design which features thicker bezels on the inner screen and more rounded corners ¹.