I ask my self if a neutral white or dark grey (depending of os setting) background color would not fit better the use case than the grey-violet-gradient or any other opinionated color 
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Would a transition from empty tab background color → grey+violet → e.g. yellow or dark blue (dapp background) be perceived as more flashy or destruptive than empty tab bg color → white → yellow or dark blue?
Just thinking out at loud, I for sure welcome the screen being restyled and this can be tested.
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I also notice the above designs use custom fonts. I would be careful about this - i.e. the sw should not become slower because it has to download a font. Same btw. for the resources or animations.