[tor-bugs] #14429 [Tor Browser]: Automated rounding of content window dimensions

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#14429: Automated rounding of content window dimensions
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     Reporter:           |      Owner:  arthuredelstein
  arthuredelstein        |     Status:  needs_revision
         Type:  defect   |  Milestone:
     Priority:  normal   |    Version:
    Component:  Tor      |   Keywords:  tbb-fingerprinting-resolution, tbb-
  Browser                |  torbutton, tbb-4.5-alpha,
   Resolution:           |  TorBrowserTeam201503R, GeorgKoppen201503R
Actual Points:           |  Parent ID:
       Points:           |
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Comment (by arthuredelstein):

 Replying to [comment:50 gk]:
 > Replying to [comment:48 gk]:
 > > Replying to [comment:47 arthuredelstein]:
 > > > There is no way for the browser to know about this discrepancy. We
 can easily fix the discrepancy with a single call to rebuild, *unless* the
 user is still holding the mouse down. So we need to keep calling rebuild
 periodically, until we can be sure the user is no longer holding on to the
 drag event. The only way to be sure of this is if a mouseover is detected.
 So we keep calling rebuild every 250 ms until a mouseover happens.
 > >
 > > But what if I use the browser mainly via keyboard (as I often do e.g.)
 or if someone is just loading a page and leaving the computer for quite a
 while? This behavior made my log grow quite quickly. I wonder even if
 scripts could detect this additional continuing load under certain
 circumstances given high precision JS timers. How expensive is this
 operation?
 >
 > Just to give some data: I can easily see that updateDimensions() is
 called 50 times a second. Oh, and moving the mouse on the window does not
 always stop that problem . Not sure in which cases this happens, though.

 Phooey, that is not supposed to happen. I discovered a mistake in my code
 that loads the resizing code once per tab instead of once per window.
 Here's my patch for review:
 https://github.com/arthuredelstein/torbutton/commit/e083a635ee8e4287ee8b5df1f4c548f041baa4db

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/14429#comment:52>
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