The change to the data module made here: https://github.com/jquery/jquery/pull/4603/files#diff-38fa4ad21a97c2bf8d5b91d033df3335 breaks projects that depend on `hasOwnProperty()` function availability. An example: https://github.com/snapappointments/bootstrap-select/issues/2430 Many other project can be affected as well. Such change should not be introduced as a minor version upgrade.