Unable to cancel task if an image has a custom Image Processor

[oillada]

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Issue Description

I'm trying to cancel a download task for an image, but when I use a custom processors, there is no task available to cancel. However, when I try with images without processors, the download task appears and can be canceled.

Reproduce

Try to cancel a request with an image processor apply to it.

Other Comment

I know that process identifiers are used for cache management; otherwise, the image is not removed. However, in this case, none of the methods receive a process ID.