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New features:
* The MuPDF program can now be used to calculate the crops. This is done
in-memory, and tends to be fast. It requires PyMuPDF to be installed in
Python -- it is already installed with the GUI option, or can be
user-installed enable the option without the GUI dependencies. This is now
the default method of cropping if PyMuPDF is detected and importable. To
force using this method, use the ``--calcbb m`` or ``-c m`` option.
* The preferred way to select the method of calculating bounding boxes has
changed. Use ``--calcbb`` or the shortcut ``-c`` with one of 'm' (MuPDF),
'p' (pdftoppm), 'gr' (Ghostscript rendering), or 'gb' (direct Ghostscript
bounding box calculation) as the argument. The default selection sequence is
'd'. Passing 'o' reverts to the older (before MuPDF) default sequence.
* The default rendering resolution is now 72 dpi instead of 150 dpi.
Resolution can still be set with the ``-x`` and ``-y`` options.
* A new option flag ``--percentText`` which changes the interpretation of
the percentage values passed to ``--percentRetain`` and ``--percentRetain4``.
With this flag the left and right margins are set to a percentage of the
bounding box width and the top and bottom margins are set to a percentage
of the bounding box height.
Bug fixes:
* Remove a debug print statement of bounding boxes that was left after a 0.2.10
negative-threshold fix.
* Fixed bug in ``--version`` argument.
* Improved sizing of GUI windows.