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HTMLDetailsElement: open property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.
The open property of the
HTMLDetailsElement interface is a boolean value reflecting the
open HTML attribute, indicating whether the <details>'s contents (not counting the <summary>) is to be shown to the user.
A boolean value.
The boolean value represents the state of the open HTML attribute. The value of true means it is set with both the summary and the additional information shown to the user. The false value means it not set, with only the summary shown.