I am new using Tor Browser Bundle. Before, I never noticed Gmail tries to use the HTML5 canvas. (Tor Browser warns this when logging into Gmail.) What do they want to do with the canvas?

closed as off-topic by Sam Whited Dec 4 '14 at 13:24

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question does not appear to be about Tor, within the scope defined in the help center." – Sam Whited
If this question can be reworded to fit the rules in the help center, please edit the question.

  • Interesting, I can't find the canvas any where in Gmail source. I'm not using Tor though. I don't think not allowing the canvas will restrict any functionality of Gmail, so don't allow the HTML5 Canvas as it only allows for the possibility of security vulnerabilities. – Cammy_the_block Nov 4 '14 at 0:56
  • I have no real information on the matter, but I assume it's for tracking. Canvas objects are quite commonly used for browser fingerprinting by ad networks as an alternative to cookies, but this doesn't really have anything to do with Tor (other than the fact that you happened to be using TBB at the time). – Sam Whited Nov 6 '14 at 14:48