TextMetrics: actualBoundingBoxDescent property

The read-only actualBoundingBoxDescent property of the TextMetrics interface is a double giving the distance from the horizontal line indicated by the CanvasRenderingContext2D.textBaseline attribute to the bottom of the bounding rectangle used to render the text, in CSS pixels.

const canvas = document.createElement("canvas");
const ctx = canvas.getContext("2d");
const text = ctx.measureText("foo"); // returns TextMetrics object

text.actualBoundingBoxDescent; // 0;