I've noticed that none of the official themes include a search option anymore

Themes
1

Also, SearchinGhostEasy no longer works on all the posts like it should.

Did version 5 break all previous search engines?

What are you all using for a search in your blog nowadays?

2

Here are all the free ones I’m aware of that folks are using…

Fuse.js
Ghost Finder
Ghost Hunter
Ghost Search
SearchinGhost
Lunr.js
MiniSearch