

Color codes will pass through pipes just like any other output.
In this case, your grep is being smarter than you want and actually parsing the incoming color codes itself.
You can try a simpler program like head
, tail
, or even sed -n /ii/p
to see it for yourself.
You can also control GNU grep’s color processing with --color
but you may not find exactly what you seek.
Syncthing may not have its own Web-based file browser but a regular Web server (like Apache or ngninx) can show a list of files in a directory without much configuration. Just point it at a shared folder. You could configure a fancier file browser like Filestash, File Browser Quantum, or even Nextcloud if you feel it’s worthwhile.
Likewise, Syncthing may not have its own concept of a “main” hoster, but it doesn’t need to: you can decide what “main” means to you. Perhaps the one you designate “main” has different ignore patterns, or a longer retention policy.
“Keeping some files remote” can be simply making sure your ignore patterns are set how you want them, if that works for you.