I’m not sure about the taskbar-style compose dialog (I also find it strange in Gmail), but generally I really like where Mastodon is going design-wise.
For accent colors/custom themes I will once again bang the drum: modern CSS is so freaking powerful! You can do a ton of color science stuff when given even a single accent color; the Mastodon web client should 100% be built around that assumption to enable arbitrary accent colors while guaranteeing minimum levels of contrast.
#Mastodon
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