Deleting / marking 404 errors as solved

Hi!

First of all, congrats for a very useful plugin! Second, I have 2 questions:

1. I have the 404s tab with a bunch of 404 errors. I import a csv file with a few redirects. The 404 errors still appear in the 404s tab. Is there a way to mark the ones I redirected as resolved and only see the remaining errors?

2. What happens when I delete a 404 error in the 404s tab? It just means I ignore the error but it still exists?

Thanks!