GL_ARB_compute_variable_group_size on i965.
GL_EXT_depth_bounds_test on Iris.
GL_EXT_texture_shadow_lod on radeonsi, nvc0.
GL_NV_alpha_to_coverage_dither_control on radeonsi
GL_NV_copy_image on all gallium drivers.
GL_NV_pixel_buffer_object on all gallium drivers, i915, i965, swrast.
GL_NV_viewport_array2 on nvc0 (GM200+).
GL_NV_viewport_swizzle on nvc0 (GM200+).
VK_KHR_shader_non_semantic_info on Intel, RADV.
GL_EXT_draw_instanced on gles2
VK_KHR_8bit_storage for ACO on GFX8+
VK_KHR_16bit_storage for ACO on GFX8+ (storageInputOutput16 is still unsupported)
shaderInt16 for ACO on GFX9+
VK_KHR_shader_float16_int8 for ACO on GFX8+ (shaderFloat16 is still unsupported)