Like many others, I created accounts on a few different instances to try things out. Using apps like Liftoff and Jerboa make it very convenient to switch between accounts, but I’ve noticed that I get different posts showing up when browsing All, even with the same sort settings.
Can someone explain why that would be? I don’t think any of the instances I’m on are defederated, so shouldn’t I see the same posts across different instances?
Not every instance communicates with every other instance in existance. Some instances ‘know about’ other instances while other instances do not. One instance has to interact with another directly first for them to discover eachother. This is a problem for smaller instances that don’t have as much cross interaction going on. Also some instances are blocked such as nsfw depending on the admins set rules for aggregation.