chromium/components/policy/resources/templates/policy_definitions/Miscellaneous/BeforeunloadEventCancelByPreventDefaultEnabled.yaml

caption: Control new behavior for the cancel dialog produced by the beforeunload event
default: null
desc: |-
  This policy provides a temporary opt-out for two related fixes to the behavior of the confirmation dialog shown by the beforeunload event.
  When this policy is Enabled, the new and correct behavior will be used. When this policy is Disabled, the old and legacy behavior will be used. When this policy is not set, the default behavior will be used.
  This policy is a temporary workaround and will be removed soon.

  New and correct behavior: In `beforeunload`, calling `event.preventDefault()` will trigger the confirmation dialog. Setting `event.returnValue` to the empty string will not trigger the confirmation dialog.

  Old and legacy behavior: In `beforeunload`, calling `event.preventDefault()` will not trigger the confirmation dialog. Setting `event.returnValue` to the empty string will trigger the confirmation dialog.
example_value: true
features:
  dynamic_refresh: true
  per_profile: true
future_on:
- fuchsia
items:
- caption: Show cancel dialog when event.preventDefault() is called for beforeunload event. Do not show cancel dialog when event.returnValue is the empty string for beforeunload event.
  value: true
- caption: Do not show cancel dialog when event.preventDefault() is called for beforeunload event. Show cancel dialog when beforeunload event.returnValue is the empty string for beforeunload event.
  value: false
- caption: Use default behavior of feature rollout plan.
  value: null
owners:
- [email protected]
- [email protected]
schema:
  type: boolean
supported_on:
- chrome.*:117-
- chrome_os:117-
- android:117-
- webview_android:117-
tags: []
type: main