D17384 has just landed, making search configuration much more powerful. Just filing this to keep track of followups.
[ ] Write an "Upgrading: ..." guidance task with narrow instructions for installs that are upgrading.
[ ] Do we need to add an indexing activity (T11932) for installs with ElasticSearch?
[ ] We should more clearly detail exactly which versions of ElasticSearch are supported (for example, is ElasticSearch <2 no longer supported)? From T9893 it seems like we may //only// have supported ElasticSearch <2 before, so are the two regions of support totally nonoverlapping and all ElasticSearch users will need to upgrade?
[ ] Documentation should provide stronger guidance toward MySQL and away from Elastic for the vast majority of installs, because we've historically seen users choosing Elastic when they aren't actually trying to solve any specific problem.