[tor-bugs] #18195 [Tor Browser]: Add a flag to identify Tor Browser in JS

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#18195: Add a flag to identify Tor Browser in JS
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 Reporter:  pento        |          Owner:  tbb-team
     Type:  enhancement  |         Status:  new
 Priority:  Medium       |      Milestone:
Component:  Tor Browser  |        Version:
 Severity:  Normal       |     Resolution:
 Keywords:               |  Actual Points:
Parent ID:               |         Points:
  Sponsor:               |
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Changes (by mcs):

 * cc: brade, gk (added)


Comment:

 Thank you for filing this ticket. I think this explains a lot of use of
 the canvas getImageData() method on websites where we (the Tor Browser
 developers) would not expect to see it used. I found this article that
 explains the technique a little:
  http://crocodillon.com/blog/parsing-emoji-unicode-in-javascript
 (it relies on the fact that the canvas fillText() method apparently
 renders nothing for characters that it cannot display).

 If WordPress detects that Tor Browser is in use, will you assume there is
 no native emoji support in the browser? It would be nice if there was a
 better solution.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/18195#comment:5>
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