0.10.0b1: Color Grading no longer supports Alpha/Transparency #493

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Description

When Color Grading is used with Alpha/Transparency, it slowly builds up over time resulting in warped images. This seems to be a regression.

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System Information

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• Software Version: 0.10.0b1
• Operating System: [e. g. Windows, Debian, Ubuntu, RedHat, FreeBSD, ...]
• Kernel Version: [e. g. 1903/1809 (Windows), 4.12 (Linux), ...]
• CPU: [e. g. Intel i7, AMD Zen2, Qualcomm, ...]
• GPU: [e. g. Nvidia RTX 2xxx Series, AMD Radeone 5xxx Series, ...]
• RAM: [e. g. 16GB, 32GB, 64GB, ...]