Cache "seen" posts and don't show them

[reggi]

I find I open up mastodon once or twice a week, scroll for a couple minutes then will lose my tab or close it out come back to it scroll for a little seeing new posts, but then slowly flow into all the posts I already saw.

This is a sign of the times with attention spans and doom scrolling with tiktok, instagram and twitter which all don't have this behavior, all showing algorithmically targeted content.

There's something to be said about the sanctity of the reverse-chronological timeline, I get it.

The feature request would be to store a cache in localstorage of "seen" posts, posts that have entered the visible window frame (and left it), and just hide them from the timeline on subsequent requests. This could ideally be a toggleable setting and not the default behavior.

[stackblitz]

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