The title is too sensationalized. It leaks the names of IndexedDB databases. This can in cases where the names follow a known pattern be used to infer domains

The title is too sensationalized. It leaks the names of IndexedDB databases. This can in cases where the names follow a known pattern be used to infer domains of other websites in the session and, in the case of YouTube, your Google id which can be used to identify your Google account. The vulnerability doesn't leak all your browsing history. It leaks a small part of it edit: title is changed now