It has so happened upon accidental closure of a tab or window with unposted content in a topic.
This is not the same as the Chrome alert for forms:
Leave the site
Changes you made may not be saved
…
As well frequented sites now commonly use a listener on the control wherein page closure gets something like this JS “are you sure” popup, the event not being quite within the purview of WP cache handling, where to go?
The same treatment applied for unposted text in the topic title is preferred, albeit of less consequence.
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