The desktop version runs in low resolution and the web version does not detect Xbox joysticks well
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It looks like that the game changes your resolution. The UI isn't supposed to be blurry. I'm about to add some resolution options in the next update.
I know that the web version doesn't work with gamepads. It has something to do with the way the input system is configured. Consider the web version as a demo. It's to give you an idea what the game is all about.