I checked out the file it flashes, and it's just an animation. I've only seen the boot animation by Chainfire that shows the logcat/dmesg while it's booting. I haven't tried it on my XZU yet though. Here's a link if you'd like to check it out. Link
Nevermind, it looks like it won't work on Xperia devices...
As we’ve mentioned quite a few times in the past, multiboot is quite the interesting … more
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