Scattter Type Text styling

I am trying to plot a chart of alarms generated by the machines on a time series scale and I have been able to do it successfully.

The thing I am not able to able to find is how can I have a border or change the background color of the scatter text that has been plotted? Is there any predefined tool for it? or is there a way do achieve it.

The only available styling options are family, size and color.

It would be really helpful to have the way to Border out or change background color of the plotted text so that we can plot boxes directly without using markers and it looks aesthetic.


Needed Output:
Required Output