The Closo extension is the small icon in your Chrome toolbar that does the unglamorous work of crosslisting on Poshmark, Vinted, Depop, and Mercari. It does four things and four things only.
First, it reads marketplace cookies from your Chrome session so Closo can post on your behalf without you re-typing your password. Second, it keeps those connections alive: it captures fresh session cookies as you browse the marketplaces normally, and it proactively refreshes a session before it expires (it fires when roughly 20% of the session's remaining life is left, debounced to once per 60 seconds). Vinted is the one marketplace with a scheduled browser-side refresh, which runs about every 30 minutes while Chrome is open. Third, it receives queued tasks from Closo — for example, list this item — and runs them in your active Chrome tab. Fourth, it sends marketplace responses back to Closo so your listing status updates appear in real time on the Closo dashboard.
What the extension does NOT do
The extension only runs on the marketplaces you connected — closo.co, poshmark.com, vinted.com, depop.com, mercari.com, ebay.com, shopify.com. It does not read pages outside that list. It does not have access to passwords, payment cards, or anything you type on any other site. And it does not run when Chrome is closed.
You need the extension installed
Connection upkeep and crosslisting happen through the extension in your own browser, on every plan and every account today. Keeping your marketplaces connected relies on the extension being installed and on you signing into those marketplaces in Chrome from time to time — that browsing is what lets Closo capture and refresh your sessions. The work reaches Poshmark, Vinted, Depop, and Mercari from your account, using your real browser, rather than from a separate server.
Permissions, explained
When you install the extension, Chrome will ask you to grant a few permissions. Here is exactly what each one is for.
Read and change data on closo.co and marketplace sites
Display notifications
Storage
Tabs
Keep your extension healthy
Pin the extension to your Chrome toolbar so you can see the icon at a glance. The icon is green when everything is fine, yellow when a marketplace needs attention, and red when something is broken. Chrome auto-updates the extension in the background — no action needed.
If a marketplace shows yellow in your sidebar or the extension icon glows yellow, click the icon and use the Connect button to refresh that marketplace's session. This usually takes 30 seconds.
Install the extension