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Starting in Firefox version 142, Mozilla released a “Link Previews” feature.

While the feature is problematic, commenters post pointed out that some previews are helpful – e.g. on Wikipedia, where a preview will appear when people hover over a wiki-linked page.

Other commenters pondered about some minimal way to replicate this elsewhere, and it seemed to be worth investigation. Read on as I propose an enhancement to the Fediverse (and maybe even web standards) to make Link Previews great: the Link Preview Manifest.

This will just lead to more requests being made.

Also anonymous requests, like those done by Mastodon to generate previews should be cached at the CDN or web server level, making them inexpensive to serve.

@yoasif interesting proposal, I have been thinking about Link Previews for clients, a typical concern there is CORS. But I didn’t see anything addressing that in the proposal.

It really feels like you didn’t read my post. I specifically called out caching as a concern, and even if we see more requests, they will be cheap to serve.

I definitely did read it.

This idea is so bad that I’m not even going to bother elaborating.

I think the previews should be federated along with the activity. The main issue described by itsfoss and the mastodon bug is not about previews themselves generating a lot of traffic but federated nature of fediverse multiplying the number of requests. If along with the post/toot/w-v the preview got sent out too, that might ease the load on the publishing host

Okay - it would have been nice to learn where the proposal fails, but I understand that I can’t access your expertise for free. Take it easy!

One thing that I neglected to mention is that since the SRI hashes are calculated, previews can be cached by peers other than the originating host - since they are verifiable, anyone can pass them along and the client can verify the payload.

Not something I really fleshed out in discovery, but if there is interest, that might make it more production ready.

Man, I am a cranky bastard sometimes. Shouldn’t post when I’m tired.

How about - the origin server, the place where the post was originally created, gets all the metadata (og:image, og:title, etc) and includes that in the Activity that tells other instances about the post? That way there is only one request made to the link and receiving instances can use that to make their preview?

It does mean that receiving instances will need to trust the sender so there’s potential for some misrepresentation but that seems acceptable to me.