You can now have the GBA startup animation on your Steam Deck with new custom boot video feature
Customizing the Steam Deck is a big part of the process for owners of the handheld PC, where users can spend hours upon hours tweaking every detail to their liking, whether it's using emulators, installing mods, or even upgrading the internal SSD. One aspect that Steam Deck users can now customize more easily is the device's boot screen animation. Valve noticed that people were going out of their way to create startup videos that replaced the typical Steam Deck logo animation, so they released a new beta update that simplifies the process.
Prior to this new client beta, custom boot animations would be wiped whenever the Steam Deck updated, but that's no longer the case. Now users can drop videos into a specific folder that the Steam Deck will try to automatically load on boot. The Steam Deck community welcomed the feature with open arms, and custom startup animations began to quickly crop up across various sites. One such place is SteamDeckRepo, which has tons of boot themes, ranging from ones that use Valve's old logo, the start screens from retro consoles like the Game Boy Advance, GameCube, or PlayStation 1, or quirkier ones that are based on anime or TV show clips. You can preview the animations over on the site, so if you're interested in making your Steam Deck look like it's booting Windows XP, or rocking a 9-second clip of the Futurama intro, you can see them all here.
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. Saves on time, soap, water and money having to wash them. 
