Line Chart with 3 week timespan has incorrect dates

[ghost]

trafficstars

Describe the bug The Line chart shows the wrong data when set to last three weeks.

To Reproduce Create a line chart widget with time span three weeks.

Expected behavior Show data of the last three weeks.

Screenshots Desktop (please complete the following information):

• OS: Mac OS
• Browser: chrome
• Version: 74.0.3729.157