The lang attribute specifies the primary language used in contents and attributes containing text content of particular elements.

An expression statement is an expression used in a place where a statement is expected. The expression is evaluated and its result is discarded — therefore, it makes sense only for expressions that have side effects, such as executing a function or updating a variable.

The lengthAdjust attribute controls how the text is stretched into the length defined by the textLength attribute.

The divisor attribute specifies the value by which the resulting number of applying the kernelMatrix of a <feConvolveMatrix> element to the input image color value is divided to yield the destination color value.

The new.target meta-property lets you detect whether a function or constructor was called using the new operator. In constructors and functions invoked using the new operator, new.target returns a reference to the constructor or function that new was called upon. In normal function calls, new.target is undefined.

The bias attribute shifts the range of the filter. After applying the kernelMatrix of the <feConvolveMatrix> element to the input image to yield a number and applied the divisor attribute, the bias attribute is added to each component. This allows representation of values that would otherwise be clamped to 0 or 1.

The class keyword can be used to define a class inside an expression.

The logical AND assignment (&&=) operator only evaluates the right operand and assigns to the left if the left operand is truthy.

The flood-color attribute indicates what color to use to flood the current filter primitive subregion.

The strict equality (===) operator checks whether its two operands are equal, returning a Boolean result. Unlike the equality operator, the strict equality operator always considers operands of different types to be different.