Description:
It would be useful, if the user could select multiple (more than one, but not all) data points in charts, for example to change its color. But there’s no such option. Clicking with Ctrl also doesn’t work, it selects only one data point

Steps to Reproduce:
1.	Open the attached file
2.	Click on the chart
3.	Double click on data point
4.	Double click on another data point


Actual Results:
Double-clicking on a new data point changes selection for the new and the previous data point loses its selection.

Expected Results:
After clicking on a new data point, the previous data point selection should be preserved.


Reproducible: Always


User Profile Reset: No



Additional Info:
LibreOffice details:
Version: 6.4.4.2.0+ (x64)
Build ID: 5c62bdca7246d3ee64fa1380c2bdc30d4c8c8481
CPU threads: 4; OS: Windows 10.0 Build 17134; UI render: default; VCL: win; 
Locale: hu-HU (hu_HU); UI-Language: en-US
Calc: