ahh! i'm so glad you enjoyed it.
honestly, i'm not too sure what might have caused the poor browser performance... we DO have a desktop build, but we've mostly not seen any problems with people running the web build. on web, the game's resolution defaults to 960x600 (and auto-matches your screen's resolution when fullscreen is active). when i play fullscreen at 2560x1440, i don't experience any performance degradation.
given the limited jam time, we weren't able to playtest on a wide range of hardware. what are your system specs? it's possible that something is misbehaving, and we just can't reproduce it with our hardware.
thank you so much for playing and for the thoughtful feedback!