Dashboard line chart PLUS bullets possible?

I have a line graph chart in my dashboard, where X is a timestamp series.
It display 4 graph lines with 800 datapoints.

var j=0;
var i=0;
var dataarray = [[],[],[],[]];

for (i = 800; i >= 0; i--) {

     dataarray[0][i] = {"x":global.get("market.data["+j+"].timestamp"),"y":global.get("market.data["+j+"].close")};
     dataarray[1][i] = {"x":global.get("market.data["+j+"].timestamp"),"y":global.get("market.data["+j+"].MFA_short")};
     dataarray[2][i] = {"x":global.get("market.data["+j+"].timestamp"),"y":global.get("market.data["+j+"].MFA_long")};
     dataarray[3][i] = {"x":global.get("market.data["+j+"].timestamp"),"y":global.get("market.data["+j+"].MFA_40")};
     j++;
}

var chart = [{
    "series":["close","MFA_short","MFA_long", "MFA_40"],
    "data":dataarray,
    "labels":[""]
}];

msg.payload = chart;
msg.topic = "test";

return msg;

I also have an array of 40 additional timestamps as a second set of data with no corresponding Y values:

[1632552397900,1632551497602,1632540996402, ...]

Is it possible to mark these timestamp positions on the existing graph with a bullet or vertical line or something else entirely, that mark those moments visually?