Instructions on how to opt-in to search! Note: you can't follow them unless your local server has updated to 4.2. To check if it has, try these options:
1) look in the bottom left-hand corner of your screen, if you're using the default Mastodon client + don't have advanced mode enabled
2) go to {your instance's domain}/api/v2/instance and look for "version" (3rd item from the top)
3) @ your admin and ask
4) follow Eugen's instructions. if they don't work, assume you're not on 4.2
