In Firefox, coloring distanced from cursor

Hi – I was going along okay in Firefox on Mac OS 10.6.3, when all of a sudden the place where the color went when I clicked became distant from where the cursor was so that I was inadvertently coloring where I didn’t want to. I’m going to try again now and see if it’s still happening.
DaisyM

Okay, I went back and tried a second time. This time I noticed that the cursor distanced after I made a mistake and hit “alt shift”. And this time after a few seconds the wild cursor placement stopped.

Just tried it in Safari. Had the same problem, but this time the distance to the color wasn’t as great. It never corrected itself. Too frustrating to continue.

I had this problem last week, so I tried using Chrome, and so far it hasn’t happened to me in that browser.

This issue is usually related to the zoom setting of your browser.  Things work great at zoom level 100% but any different and computing coordinates gets wonky.  If you hit Alt-0 or Cmd-0 on a mac, it should set the zoom back to 100%