They fucked up those portraits a while ago, I'm still seeing it.
にせがいじん
You could try setting "Block all sites from storing information on this computer" under "Local Storage Settings" in Flash global settings and closing and restarting your browser to get rid of anything stored by Flash which might not be affected by clearing the browser cache.
Change that setting back to "Allow sites to save information on this computer" if you want the game to save your sound settings.
I don't know how you get to those settings on chrome.
I have that setting on by default for everything and I don't see the image issues you have.
I use Firefox on Linux (FKG works with the really old Flash version Linux has).
No it is not smaller than other Nutaku games and there is no black box.
Linux was frozen at Flash Player 11 (with some security updates) by Adobe years ago so maybe the different flash version explains it.
It looks to be the same relative size on Chromium but the computer I tried that on has a much screen lower resolution so that is not an exact comparison.
That computer is really slow so I set quality to low in flash to get it to run less slow so I can't say if it had issues with image quality.
I've got the same issue here, though it only seems to be distorted in the choose ally screen. I can't remember it clearly but I think it happened on the update before Robinia's event.
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