[tor-bugs] #10095 [TorBrowserButton]: Setting screen resolution to a multiple of 200 x 100 is not working reliably with patch in #8478

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#10095: Setting screen resolution to a multiple of 200 x 100 is not working
reliably with patch in #8478
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     Reporter:  gk                |      Owner:  mikeperry
         Type:  defect            |     Status:  new
     Priority:  critical          |  Milestone:
    Component:  TorBrowserButton  |    Version:
   Resolution:                    |   Keywords:  tbb-fingerprinting
Actual Points:                    |  Parent ID:
       Points:                    |
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Comment (by gk):

 I have been looking into this for the last days and have not found a way
 to solve this issue properly with extension means. The problem we face is
 described pretty well by
 https://bugzilla.mozilla.org/show_bug.cgi?id=870346#c1: The outerWindow
 dimensions are set, then the window is made visible and then depending on
 other extensions overlaying stuff the size of the innerWindow is adapted.
 Thus, having a fixed innerWindow size regardless the overlayed content of
 other extensions AND having the resizing we do not visible to the user is
 currently not possible.
 If we want to keep our current model (resizing the inner dimensions to a
 multiple 200 x 100 and faking the outer dimensions accordingly) we have a
 bunch of ad-hoc solutions for this ticket. We could:

 1) Use only small icons
 2) Craft a specific HTTPS Everyhwere icon that does not enlarge the chrome
 area anymore
 3) We could resize the window additionally with setTimeout(0)/or after
 xul-overlay-merged got fired. Thus, if the innerwindow has no multiple of
 200 x 100 anymore after other overlays got merged we would enlarge the
 window a tiny bit again which would minimize the usability impact of it
 (compared to the scenario where we would enlarge the window from its
 original size to, say, 100 x 900 having the window already visible).

 I am not happy with either of these stopgaps, though, for various reasons
 (they don't solve the underlying issue; they won't be acceptable by
 Mozilla; the user might shoot herself in the foot with installing just one
 further legitimate extension...).

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10095#comment:3>
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