This is awesome! Full text search has come to Mastodon, and it's being rolled out in a responsible way.
I know full text search is a hot-button issue. For journalists, researchers and many others, FTS is essential. Plenty of others have good reason to keep their content unsearchable.
If you're in the latter category, you don't need to take any action. Your toots will remain unsearchable just as they were before.
For the rest, please manually change the default so your toots will be searchable. This will address a major shortcoming that has kept a huge number of fedi holdouts from joining.
To do that, go to Preferences > Public Profile and select the Privacy and Reach tab. Then check the Include public posts in search results.
*** Edit: sorry, my initial post told y'all to click the wrong box. Fixed.
