That instgant speed setting would be appreciated.
Also, and this might be related to some obscure browser setting (I'm using Brave - Chromium), I'm experiencing an increase in lag, to such a degree that I have to reload the page to get rid of the lag. This occurs if I alt-tab to another program for a while and come back to the game (I have it open at work :P). By lag I mean that it takes several seconds for the browser to load an animation, missing clicks on buttons, etc. Almost like the browser clears some cache (power saving settings maybe?) while the tab is not active.
I'm playing the game in Brave on both Windows and Ubuntu OS and both have the same symptom. I don't see this lag issue if I have the browser game tab active at all times (aka. while playing the game).
Kudos to you for taking the time to make such a nice game... and free as well!