Choose and observe storage

Inspect before you change

Use browser DevTools and a clean test profile to identify storage owners, stale versions, and unexpected data.

8 minute lesson

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Storage bugs are easier when you can see the state. Open DevTools before adding more code.

Use the browser Application or Storage panel to inspect cookies, Local Storage, Session Storage, IndexedDB, Cache Storage, and service workers. The Network panel shows Set-Cookie responses and later Cookie requests.

Test with a clean origin too. Your normal profile may contain an old schema, a stale cache, or a cookie created by code that no longer exists. A private window helps isolate state, but it is not a perfect substitute for testing every supported browser.

Never share a storage screenshot or HAR file without reviewing it. Cookies, tokens, personal notes, URLs, and response bodies may be visible.

Inspect one real site you control. List every stored item, its apparent owner, and whether it survives reload, a new tab, browser restart, and clearing site data. Redact secrets from your evidence.

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