The fy attribute defines the y-axis coordinate of the focal point for a radial gradient.

The descent attribute defines the maximum unaccented depth of the font.

The yield* operator is used to delegate to another iterable object, such as a Generator.

A labeled statement is any statement that is prefixed with an identifier. You can jump to this label using a break or continue statement nested within the labeled statement.

The id attribute assigns a unique name to an element.

The opacity attribute specifies the transparency of an object or of a group of objects, that is, the degree to which the background behind the element is overlaid.

The from attribute indicates the initial value of the attribute that will be modified during the animation.

The color-interpolation attribute specifies the color space for gradient interpolations, color animations, and alpha compositing.

The switch statement evaluates an expression, matching the expression's value against a series of case clauses, and executes statements after the first case clause with a matching value, until a break statement is encountered. The default clause of a switch statement will be jumped to if no case matches the expression's value.

The JavaScript exception "too much recursion" or "Maximum call stack size exceeded" occurs when there are too many function calls, or a function is missing a base case.