New Fedora User - Mailspring Feature Questions

After 20 yrs on Mac Mail, I have moved to Fedora and looking for an email client. I have tried Thunderbird for a few months but it’s just not up to the job (global search mainly, totally unusable). I have a few questions before trying Mailspring…

  1. Does it support LOCAL folders? I have 20 yrs of email nested in folders and nicely organised.
  2. Does the global search work?! (Will it search ALL folders, local and imap, for the query I enter?)
  3. How easy is to migrate Thunderbird to Mailspring?

Thanks