When sharing on Sync, it always shares a link to whatever instance the community is on, or sometimes even the instance your home instance federated the post from, meaning I can be looking at a post from lemmy.world, from my home instance of lemmy.ca, and the share link will be from yiffit.net.
Is there a way to always share a post as coming from your home instance?
Yes, you are viewing the post that was made on Lemmy.ca, federation allows you to see posts on other instances. You are able to see the post and comment because of federation, lemmy.world grabs a cached copy to show it’s users, the actual post is still on the original server. If you want to share a post, and let others interact in the comments, the link needs to be to the actual post. If you just want them to see something, and not know where it came from, a screenshot might be better.
You can interact with the post if you’re signed up to Lemmy.ca, which the users I’m sharing the posts with are.
I can’t interact with the post from lemmy.world’s site if I don’t have a lemmy.world account.
And realistically, you would only want to share content through your own instance, as it’s the only instance you’d want to vouch for and can guarantee it is free of advertising, lewd UI themes (ahem, yiffit), bad redirects, or anything that could weird out someone visiting the content you’re sharing with them. There’s also the “you always send me links from random websites” factor, and people are rightfully hesitant to click on links from domains they’ve never seen before. If they know person X always shares posts federated to their own instance, they’ll be more likely to trust the link.