The JavaScript exception "missing variable name" is a common error. It is usually caused by omitting a variable name or a typographic error.

The x attribute defines an x-axis coordinate in the user coordinate system.

The JavaScript exception "class constructors must be invoked with 'new'" occurs when a class constructor is called without the new keyword. All class constructors must be called with new.

The JavaScript Guide shows you how to use JavaScript and gives an overview of the language. If you need exhaustive information about a language feature, have a look at the JavaScript reference.

The u2 attribute specifies list of Unicode characters (refer to the description of the unicode attribute of the <glyph> element for a description of how to express individual Unicode characters) and/or ranges of Unicode characters, which identify a set of possible second glyph in a kerning pair.

The JavaScript exception "parameter after rest parameter" occurs when a rest parameter is followed by anything else in a parameter list, including another rest parameter, a formal parameter, or a trailing comma.

The xChannelSelector attribute indicates which color channel from in2 to use to displace the pixels in in along the x-axis.

The stdDeviation attribute defines the standard deviation for the blur operation.

The JavaScript exception "await is only valid in async functions, async generators and modules" occurs when an await expression is used outside of async functions or modules or other async contexts.

The JavaScript exception "missing : after property id" occurs when objects are created using the object initializer syntax. A colon (:) separates keys and values for the object's properties. Somehow, this colon is missing or misplaced.