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The BooleanDelta type of the downloads API represents the difference between two booleans.


Values of this type are objects. They contain the following properties:

A boolean representing the current boolean value.
A boolean representing the previous boolean value.

Browser compatibility

ChromeEdgeFirefoxFirefox for AndroidOpera
Basic supportYesNo47.048.033


This API is based on Chromium's chrome.downloads API.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, wbamberg
 Last updated by: chrisdavidmills,