Chrome gives extensions two places to store data: synced storage (mirrors across all your Chrome installs via Google) and local storage (stays on this device only). For most extension data, synced is the right default. For your marketplace session tokens, we re-evaluated and switched to local.
What was the risk
Synced storage isn't insecure — it's encrypted in transit and at rest in Google's infrastructure. But it does mean a copy of your marketplace session tokens lived in your Google account. If a household member used your Google login on a shared computer, the extension could pull the same tokens onto that computer. Same if you ever signed into Chrome on a public terminal.
This wasn't a high-likelihood risk for most sellers, but the impact if it did happen was real — those session tokens are what authenticate you to the marketplaces. We decided the convenience of cross-device sync didn't outweigh the blast radius.
What changed
On extension version 3.10.67 and later, your marketplace WebSocket and session tokens are read from and written to chrome.storage.local instead of chrome.storage.sync. Existing data on your current device gets migrated automatically the first time the new version runs.
Functionally, you notice nothing. The extension still remembers your settings, still keeps you logged in, still works across browser restarts. The only change: switching to a new computer no longer auto-loads your old marketplace tokens. You'll log into marketplaces once on the new machine, then it's set.
What you need to do
Almost nothing. If you've recently switched to a new Chrome install (a new computer, a fresh OS install), log into Closo and re-link your marketplaces once. That's it.
If you're seeing 'session not found' or 'unauthorized' errors that won't clear, that's the most likely cause — your tokens didn't sync to the new device. Re-link and you're set.
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