I bought an iPhone 8 to replace my iPhone 6. I was able to migrate absolutely everything via the "Quick Start" functionality.
However, when I opened WhatsApp on my new phone, all the media sent via WhatsApp was gone. For example, I had a collection of "starred" GIFs that now is only displayed as a bunch of items without an image, and when I try to select one of them I get a "This item could not be selected. please choose a different item" error message.
How can I recover the WhatsApp media (including the GIFs) from my previous phone? I still have the iPhone 6 with all its data.