Add a user setting to automatically mark fetched posts (list_posts) as read.

[dessalines]

Requirements

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Is your proposal related to a problem?

Users want the ability automatically mark posts in their feed as read, without having to manually click into the post, or click a mark read button.

Currently, a few apps are doing this by collecting up ids, then when its scrolled to the bottom, send a list of post ids to the mark_read function. But #5043 takes this away, in exchange for returning the full post result.

At the same time, collecting up ids isn't the cleanest solution, and most apps probably don't want to code this. We also don't want to spam a lot of individual, or collected requests.

Describe the solution you'd like.

Add a user-setting to automatically mark fetched posts (the posts received back from list_posts, as read.

Pros

• Easy to implement on the front and back-end, requires no more than adding the setting.
• No more spamming mark read.

Cons

• A large fetch size might mean that some posts that weren't seen (beyond the scrolling / visible region), will get marked as read, even though they weren't seen.

Describe alternatives you've considered.

NA

Additional context

#5043 (comment)