How can I use the Gitlab CDN adapter with the Azure Standard CDN, which does not offer ETag

Question

Gitlab's external storage for static objects has the potential to speed up an instance substantially and off-load a lot of work. I have access to the Azure CDN Standard Microsoft product, but not the more expensive versions.

The Protocol definition requires an ETag return value. My problem is that:

Azure CDN Standard/Premium from Verizon supports ETag by default, while Azure CDN Standard from Microsoft and Azure CDN Standard from Akamai do not.

Does anyone know if the Gitlab CDN adapter can be implemented without ETag? If so, how?