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 # CHANGELOG - sitespeed.io  (we use [semantic versioning](https://semver.org))
 
+## 28.0.0 - UNRELEASED
+
+### Breaking change
+There where a bug in how the `browsertime.pageSummary` message was created where data was attached to the browserScript key (for example, the HAR file was attached to the element). This has been fixed and everything will work as before except if you have created your own plugin and listen to `browsertime.pageSummary` messages and where using the faultu attached data.
+
 ##  27.9.3 - 2023-06-19
 ### Fixed
 * Upgraded Browsertime with the following fixes: