As of version 2.3 Unigine Sanctuary needs GL_ARB_half_float_pixel. This extension is supported by hardware, but there may be some patent issues, more info in this comment: https://bugs.freedesktop.org/show_bug.cgi?id=28294#c11 .
Fixed with commit 73e8a2738743035e1347571ba630747d2ec33a2d. Closing..
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