changes-5.12.0

Qt 5.12 introduces many new features and improvements as well as bugfixes
over the 5.11.x series. For more details, refer to the online documentation
included in this distribution. The documentation is also available online:

https://doc.qt.io/qt-5/index.html

The Qt version 5.12 series is binary compatible with the 5.11.x series.
Applications compiled for 5.11 will continue to run with 5.12.

Some of the changes listed in this file include issue tracking numbers
corresponding to tasks in the Qt Bug Tracker:

https://bugreports.qt.io/

Each of these identifiers can be entered in the bug tracker to obtain more
information about a particular change.

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*                                   TIFF                                   *
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 - A number of security-related upstream patches has been applied to the
   bundled libtiff
 - Added reading support for 16 bits per channel (rgb48/rgba64) files
 - [QTBUG-70820] Larger strip size when writing, for improved compression

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*                                   WebP                                   *
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 - [QTBUG-48628] Retain non-alpha format on reading and writing.
 - Use default compression setting for lossless (quality==100) writing

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*                             Third-Party Code                             *
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 - The unmaintained bundled libmng has been removed. Building the mng
   handler will require libmng to be present as a system or external
   library.
 - The unmaintained bundled libjasper has been removed. Building the jp2
   handler will require libjasper to be present as a system or external
   library.