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+=======================
+Command Line Parameters
+=======================
+
+Firefox recognizes many (many!) command line parameters.  Overview
+documentation of these parameters lives here.
+
+Known parameters
+----------------
+
+.. list-table::
+   :widths: 20 80
+   :header-rows: 1
+
+   * - Parameter
+     - Description
+   * - ``-osint``
+     - On Windows, ``-osint`` serves two purposes.  Most importantly, it signals
+       that the command line is untrusted and must be sanitized.  Command lines
+       with ``-osint`` are rejected unless they have a very specific structure,
+       usually ``firefox.exe -osint -url URL`` or ``firefox.exe -osint
+       -private-window URL``: refer to `the EnsureCommandLineSafe function
+       <https://searchfox.org/mozilla-central/rev/ead7da2d9c5400bc7034ff3f06a030531bd7e5b9/toolkit/xre/CmdLineAndEnvUtils.h#196>`_.
+       These command lines are produced by apps delegating to Firefox, and the
+       resulting URL may not be correctly quoted.  The sanitization process
+       ensures that maliciously chosen URLs do not add additional parameters to
+       Firefox.  Secondarily, the ``-osint`` parameter signals that Firefox is
+       being invoked by Windows to handle a URL: generally a registered file
+       type, e.g., ``.html``, or protocol, e.g., ``https``.