backbone.js - Why is this DOM element shown greyed-out and isolated in Firebug? -

i have backbone application appends elements dom. when log these dom elements console, appear greyed-out , isolated in firebug inspector, this:

other times, shown in full colour , within context of dom. here same element, @ different time in backbone app:

i'm guessing greyed-out, isolated treatment denotes element not appended dom—but i'm troubleshooting bug in app , helpful 100% sure.

you guessed right. "greyed-out" element detached dom.

Funaction