Looking at the world repo, most Qt5 packages are 5.15.10. However, qt5-webengine is 5.15.14. However, many of the files in the package are 5.15.13. As far as I can tell, 5.15.10 is the latest version actually released by Qt. Is there any reason for the odd numbering?
It's just how upstream works: https://code.qt.io/cgit/qt/qtwebengine.git/log/?h=5.15.14
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