Every tutorial sells you the same fantasy. A weekend, a manifest.json, a popup — and you publish a Chrome extension with a neat little "published" badge. The coding part of that story is roughly true. Everything after the last commit is where the fantasy quietly dies.
In 2026 there's a wrinkle: if you're one of the developers working with LLM agents, even the "after the last commit" part has shrunk. An agent drafts your store copy, localizes it into forty locales, and produces a first-draft privacy policy in an afternoon. What it can't do is wait in the queue for you — or answer to a reviewer for artifacts it generated on your behalf.
That's the part where your extension actually becomes available to users. I've watched enough extensions go through store review to say it plainly: publishing is not one step.
It's a gauntlet. Three gates, a queue, a reviewer, and a clock that restarts every time you get something wrong. Here's what that gauntlet looks like in 2026.
First, some perspective on the queue you're joining. According to Chrome-Stats, which tracks the store continuously, the Chrome Web Store held roughly 303,800 extensions as of August 2026. Mozilla's directory counts over 74,000 Firefox add-ons as of January 2026, and community trackers put the Microsoft Edge add-ons catalog at around 31,000.
| Store | Extensions tracked, mid-2026 | |---|---| | Chrome Web Store | ~303,800 | | Firefox (AMO) | 74,000+ | | Microsoft Edge | ~31,000 |
Sources: Chrome-Stats (Aug 2026), Wikipedia (Jan 2026), r/chromeextensions cross-store tracker.
One tracker on r/chromeextensions counted 49,518 new Chrome extensions in a single quarter — more than the entire Edge catalog. Your extension isn't entering a curated gallery. It's entering a queue that gets longer every week, and it's being judged by systems built to cope with that flood.
That flood has a new tributary: agent-assisted development has collapsed the cost of producing a working extension to an afternoon, and the queue is filling accordingly. Your extension isn't just competing with 303,800 existing ones — it's competing with everything else agents shipped this week.
Here's what tutorials skip entirely: the upload button is not the first step. It's step thirty.
Before you can even open the developer dashboard, you need to produce a small media production. Four icon sizes (16, 32, 48, 128 pixels for Chrome, a slightly different set for Firefox and Edge). At least one screenshot per store at a minimum of 1280×800 or 1280×720, though the stores recommend more. Chrome asks for promotional tiles — a 440×280 small promo, a 920×680 marquee, and a 1400×560 large marquee — if you ever want to be featured.
Then the copy. A short description (132 characters for Chrome, 250 for Firefox). A detailed description in markdown, ideally with keywords researched against what your competitors rank for. A privacy policy URL that actually matches what your extension does, not a generic template that says "we collect nothing" while your analytics SDK quietly collects everything. A homepage URL. A support URL. A support email.
If you're serious about distribution, you need that copy in more than one language. Chrome Web Store supports 40+ locales, and localized listings convert dramatically better than English-only ones. That's 40 translations of your short description, your detailed description, your changelog, and your screenshots with localized UI.
Then the smaller decisions that turn out to matter. A category selection that determines which browsing surfaces surface your extension. A data declaration that lists every piece of user data you collect — Chrome's privacy disclosure form is not optional, and it must match your privacy policy. An onboarding flow that actually teaches new users what your extension does, because the store listing is marketing, not documentation.
"A week of work" is the by-hand estimate — conservative, and accurate. If you're running an LLM agent, generation is the cheap part: store copy, forty locales, a landing page, a first-draft privacy policy, an afternoon. What doesn't shrink is verification. Every generated artifact has to be checked against what your extension actually does, because the store will check it against what your extension actually does — and a plausible privacy policy that doesn't match your analytics SDK is a rejection with better grammar. The week doesn't disappear; it converts from production into review. And all of it happens before you touch the upload button, before the review queue, before the part where you wait.
This is also the part where most developers cut corners — and where the tools that exist specifically for this job earn their keep. The icon generator produces a full store-ready icon set from a prompt or an SVG, plus a promo tile and a paste-ready manifest snippet (2 free AI generations, then credit packs for volume). The SEO optimizer scores your listing copy against top competitors in your niche and suggests keyword, readability, and field-length fixes. The AI visibility tool does the same for AI assistants — scores your copy for discoverability by ChatGPT and Claude, then generates llms.txt and Schema.org JSON-LD for your extension's site. The page generator builds a polished single-page HTML landing site you can deploy anywhere.
And if you already have an agent writing your copy, generation isn't your bottleneck — grounding is. A blank-prompt agent will happily produce a generic listing; what it can't do is know that the marquee tile is exactly 920×680, that Edge's priority queue has favored certain categories since February 2025, or which keywords the current top three in your niche actually rank on. Policy-grounded tools are what keep generated output from being confidently wrong.
None of it requires a website of your own, either — which is the part tutorials really skip. The moment your extension needs a privacy policy URL, a support URL, and a homepage, you're suddenly standing up infrastructure for a product that isn't launched. It doesn't have to work that way anymore: every page these tools can produce — privacy policy, pin guide, install instructions, welcome page, uninstall survey — can be hosted for you at a stable permalink. No domain to buy before you have users, no form to build, no server to run. A GitHub Pages account is no longer part of the minimum viable launch.