The major new addition is a new GLES2 backend, meant to improve performance on low end hardware. This was written by emile_b for the Android port but backported to the mainline for old hardware support.
Please note that this backend removes some non-essential features to increase performance, like the entire postprocessing or advanced lighting features like specular or PBR.
Our tests show no performance gains on modern hardware capable of Vulkan, so is not recommended to run it on such systems - it is solely meant for old hardware that have performance issues with the modern GL backend.
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This fixes the problems reported for 2.0 and addes a few new features:

• extraction of Blood .RFF files
• no longer crashes when extracting Strife1.wad

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