Optional Tracker3 search backend

Hello Linux Mint team!

I have a feature request, would you be open to Tracker3 as an opt-in search backend in Nemo, alongside the current engine?

On my own setup search has become slow, my documents and media directories keep growing, and walking them live for every query takes long enough that I usually use a second search tool instead. Indexed search elsewhere (Spotlight, Nautilus with Tracker) returns hits as you type, I think this is nowadays the expected behavior.

I know #321 asked something similar back in 2013 and was closed in 2018, but that one wanted to replace the existing engine. I am asking the narrower question of whether Tracker3 could live next to it as an opt-in option - default off, silent fallback if the daemon is not running. The build flag for Tracker support seems to exist already (#3093, #3247), it just is not exposed at runtime.

Happy to hear from you!

Start by reviewing Nemo’s existing search backend and the Tracker support build flags referenced in #3093 and #3247. Define how an opt-in Tracker3 backend would coexist with the current engine, remain off by default, and fall back silently when the daemon is unavailable; done means indexed searches work without changing the default behavior.