Hello,
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In UWP's Splash Screen
, your app icon changes according to the window width. This is why you need to provide icons with different resolutions.
In the visual assets editor, there are corresponding resolutions under different icons, you cannot place 620 x 300 icon on 1240 x 600.
The meaning of the document is that your base zoom icon size (1x) must be 620 x 300, and other icon resolutions are enlarged based on this
Thanks.