WebGL rendering issues in Chrome

Combination of technologies results in some interesting screen rendering issues in Chrome (the last few versions). I'm curious is anyone else has come across them:

Build a page containing several jQueryUI dialogs, hidden by default.
Dynamically generate a <canvas> element within one of the dialog <section> elements, webGL context (using ThreeJS or similar wrapper).
Via script, show the dialog and render your WebGL

At this point, in Chrome (Release and Canary), moving the dialog containing the <canvas> about the screen will cause horrible screen repainting issues. Nudge a corner of the window and everything paints the way it is supposed to. Drag a dialog again, and the mess starts over.

Anyone seen this?

Interestingly, Safari doesn't exhibit this issue, so it's possibly something that Chrome is doing rather than WebKit. Also, rendering fine, if a little ugly, in FireFox (why no antialiasing FireFox!?).