What enabled the iPhone 13 to automatically save chat pictures?

You need to download the re manager.

The chat will not generate a file and save it. If it is a voice message, it will be saved in WeChat. If you want to save chats on your phone, your phone needs to be rooted and you need to download a re manager to find it.

WeChat is a free application developed by Tencent that provides instant messaging services for smart terminals. WeChat supports cross-communication operators and cross-operating system platforms to quickly send free (a small amount of network traffic is required) voice text messages, videos, pictures and text through the network.