Offer to download/cache (allowed) remote content before going offline

[Noca]

When I switch Thunderbird (Windows) to offline mode. It offers to "download messages for offline use before going offline." This appears to download my IMAP-server's messages, but not the (allowed) remote content. This is a problem for newsletters (eg, from Substack) that rely on remote content to deliver images within the message. Unless I've previously opened the message, its images don't appear in offline mode. I usually wait until I'm back online before reading those messages, which is frustrating. It kind of defeats the purpose of using offline mode.

As a workaround, I've found that opening each message in my inbox before going offline is sufficient to cache the remote content, but that's tedious. It'd be nice if the "download messages for offline use" would cache the (allowed) remote content for each message before going offline. Perhaps this could be a checkbox to give users flexibility in deciding whether they want to do this. Though truly, I can't think of a use-case where the user would want to download their messages but not the associated (allowed) remote content.

[Jon]

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