Images in emails are inconsistently being cached in iOS Outlook App
问题 While testing images being loaded from an email in my iOS Outlook app, I see inconsistencies with how the app caches them. These images are loading from external sources (i.e. HTML img tag with src pointing to a server, not images that are embedded/attached). The app makes several requests to the same image source as you navigate around. Some of these requests contain the HTTP_IF_NONE_MATCH header but there is a lot of inconsistency. I don't think it's caching them correctly. I've included