Lightroom Classic: Additional metadata : "synchronized with Lightroom"

Hi !

I would suggest to add this metadata in LR Classic in order to filter images which are "NOT synced with Lightroom" or "which belong or not in, a collection". Maybe add a line in "catalog menu", there is allready a line "synced", but not the opposite.

In case this exists allready, pls help. I didn't find any post on thge subject.

Thanks

Emm