[tbb-bugs] #16977 [Tor Browser]: Resizing Tor Browser window ruins default screen size, leaking it

[Tor Bug Tracker & Wiki]

#16977: Resizing Tor Browser window ruins default screen size, leaking it
-------------------------+--------------------------
 Reporter:  cypherpunks  |          Owner:  tbb-team
     Type:  defect       |         Status:  new
 Priority:  critical     |      Milestone:
Component:  Tor Browser  |        Version:
 Keywords:  screen size  |  Actual Points:
Parent ID:               |         Points:
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 The automated resize of Tor Browser window when using a tiling window
 manager loses the preset default screen size. Not specifying a Tor Browser
 version because this is a problem for current, 5.0.2 Tor Browser version,
 but goes back to many older versions.

 Problem can be seen on Linux with dwm-6.0 window manager.

 Steps to reproduce:

 1. Set dwm to tiled mode. Default hotkey for this is Alt-t. dwm is in
 tiled mode by default.

 2. Make sure there are no other open windows on screen.

 3. Start Tor Browser. Its window will take all available screen space
 (since there are no other windows, see 2.) By default it will set screen
 size to 1000x600, as reported by https://panopticlick.eff.org

 4. Open some other window.

 5. Window of Tor Browser gets automatically resized, so the new window can
 fit in.

 6. Make sure the Tor Browser window is active (has focus).

 7. Switch the dwm layout to monocle (full screen, so active window takes
 all available space and covers up all other windows). Default hotkey for
 this is Alt-m.

 8. Notice the Tor Browser window expanding back to full screen, yet screen
 size expanding as well and eating up all available space inside the
 browser window. After this step, https://panopticlick.eff.org reports a
 modified, bigger screen size.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/16977>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
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