I built three Chrome extensions natively on Manifest V3. Not ported — built from scratch knowing MV3 was the target. Here's what that actually means in practice.
This isn't a "MV3 is great/terrible" opinion piece. It's a list of concrete decisions I had to make and bugs I had to debug, with the code that came out the other side.
The problem MV3 solves (and why it matters to you even if you don't care about Chrome's reasons)
MV2 extensions could run persistent background scripts that had unrestricted access to network requests. This is how ad blockers worked — and it's also how malicious extensions worked. Chrome's argument for MV3 is that restricting background script behavior makes extensions less dangerous.
Whether you agree with that tradeoff or not, it's done. MV2 extensions are gone from the Web Store. If you're building extensions now, you're building on MV3.
