Hello LJDawson, let me start with saying how happy I am to have Sync back :)
The one issue I have with Lemmy is duplicated posts between different communities (see screenshot). Posts usually have same title, author and link, yet differ in community/server they are posted to. It would be great to be able to make the appear as one item on the feed with some note below that links to both instances' posts, or something like that basically to make them not appear twice or thrice one under another.
Playing devil's advocate for a bit... So these are just cross-posts. Which existed even on Reddit. ...I assume they weren't handled in any way in Sync or Reddit?
But let's say this is fixed... What to do about the multiple comments threads? How would you reconcile them with each other? Especially since the user can choose different ways to sort the comments as well. Would all of this logic normally handled by the Lemmy back-end now need to run on your phone? Also how do you choose which post / instance to actually display and which ones to hide?
Btw, I'm not trying to dismiss the idea. Just want to call out some of the technical problems that might come up trying to implement such a feature. As well as ask questions to try and determine exactly how such a feature is expected to work.
I would imagine one post preview with a very compact list of instances on which the posts were posted so that you can enter either of those posts' view.
Or merge the posts into one view, show somehow it's a merged post, and merge comments as well (and let you choose the instance on which you want to comment if you create a new top-level comment).
Reddit had similar issue but it wasn't that bad since you hardly ever had 2-4 similar communities - something that appears to be very common with decentralised lemmy.