Can you try Firefox (latest) and report back please? It could be an isolated issue for your monitor, or the chromium version you are using.
It's fine in firefox 20.0. About>Firefox doesn't report the useragent string any more it seems, just "20.0".
The version of chromium where it doesn't work right is "Version 25.0.1364.160 Ubuntu 12.10".
I tried playing in the HTML5 version, but it disconnected twice within about 5 minutes, so I switched back to the Windows client.
I was trying to chat at the time. I don't know if that's what caused the disconnections, or if that's unrelated.
I tried watching the game in firefox's HTML5 interface, but it doesn't really work. I don't know if it's because firefox's javascript engine is slower or what, but one CPU core runs pretty much flat out, and I don't get to see any community cards on the table. Also, bottom line of text on the table is half off the screen. Resizing the window often doesn't result in a redraw; presumably the code is lagging too much. Here are a couple of screenshots at different window sizes in firefox with the text off the bottom of the screen. Notice in one it has forgotten to (or not got around to) draw the player stack sizes yet:
I did eventually get to see a card on the table, but it was face down. I expect it was meant to be an animation of a player folding their cards, but it just sat still in the middle of the table for over a minute while I screenshotted it:
In Chromium, on the other hand, the animations all work fine, and I get to see the cards as I hear them. (In firefox I hear cards being dealt onto the table, but don't see them). The CPU is still high while viewing a table. It drops right down in both firefox and chromium as soon as I go back to the lobby screen. The text at the bottom of the table isn't cut off in chromium, at any size, and as I resize the window, the table scales nicely to fit (until I make it too narrow, at which point it tells me to 'rotate my device' (whatever that is meant to mean)):
