Oppo Pad Air 5 will be launched in China on December 25 as the successor to the Pad Air 2. A day ahead of its much-anticipated unveiling, a YouTube channel has uploaded a purported unboxing video of the tablet, revealing its design and in-box accessories. The upcoming Pad Air 5 is shown to ship with a 45W charging adapter, while it is confirmed to support 33W wired fa…