"Virtualization" might be the most buzzed, least understood word in frontend performance.
Every optimization discussion, someone drops it. My roommate does it every time React or Angular perfmonce comes up: "just virtualize it." So I asked him one follow-up:
"Okay — what happens to the rows that scrolled away?"
Silence. He'd never thought about it. Neither had I, honestly, until I added virtual scrolling to a lead table this week and started pulling the thread. "It only renders what fits on screen" is the marketing sentence — true, but it's maybe 20% of the mechanism. The interesting 80% is in the follow-up questions:
What happens to rows that scroll out of view?
