Kinda. You're server will not back-populate old posts from someone you just followed. However, you should get all future posts.
If you find a thread on Lemmy and you want to comment on it in Mastodon, but you can't find it normally, you can copy the URL to the thread or comment, paste it in Mastodon search, and then it should force-load that post. Then you can reply and comment on it as normal.
They could be in this very room!
Well, right now I don't use it.
But if I did I would use it to create new pages with special templates, then I can format a home page with all the buttons, and dataview queries to sort and organize the new pages.
Something like a journal where a button might be "Daily entry" and another for "New Project Page" or "New Task" or something.
It also might work really well for taking notes in DnD. (Quick "new character/place/item page" buttons right in the session notes page.) I'll have to experiment with templates again this summer.
I don't have a complex enough workflow to need a lot of plugins, but I really really like Dataview. Templater and Buttons will probably be really high on my list too if I get around to actually using them.
A lot of people saying this is a Chromium fork, but According to their blog, that's not fully the case.
So it uses Window's default web renderer. It just happens that the default renderer for windows is the same as Chromium's renderer. In this way it does mean that it has a lot of the same problems as Chromium forks, but the browser itself isn't a chromium fork. (This is also why the macOS version uses Webkit and not Blink.)