Function QLThumbnailRequestCreateContext 

pub unsafe extern "C-unwind" fn QLThumbnailRequestCreateContext(
    thumbnail: &QLThumbnailRequest,
    size: CGSize,
    is_bitmap: bool,
    properties: Option<&CFDictionary>,
) -> Option<CFRetained<CGContext>>

👎Deprecated: renamed to QLThumbnailRequest::context

Available on crate features QLGenerator and objc2-core-graphics only.