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JS
JavaScript error

TypeError

The JavaScript exception "called on incompatible target (or object)" occurs when a function (on a given object), is called with a this not corresponding to the type expected by the function.

Reference entryJavaScriptFetched
This is a reference entry from MDN Web Docs. A full explanation with fixes has not been written yet.

The error messages

TypeError: Method Set.prototype.add called on incompatible receiver undefined (V8-based)
As listed by MDN Web Docs
TypeError: Bind must be called on a function (V8-based)
As listed by MDN Web Docs
TypeError: Illegal invocation (V8-based)
As listed by MDN Web Docs
TypeError: Function.prototype.toString requires that 'this' be a Function (V8-based)
As listed by MDN Web Docs
TypeError: this is not a Date object. (V8-based)
As listed by MDN Web Docs
TypeError: this is not a typed array. (V8-based)
As listed by MDN Web Docs
TypeError: Function.prototype.toString called on incompatible object (Firefox)
As listed by MDN Web Docs
TypeError: Function.prototype.bind called on incompatible target (Firefox)
As listed by MDN Web Docs
TypeError: 'addEventListener' called on an object that does not implement interface EventTarget. (Firefox)
As listed by MDN Web Docs
TypeError: Type error (Safari)
As listed by MDN Web Docs
TypeError: undefined is not an object (Safari)
As listed by MDN Web Docs

Details

Category
TypeError
Severity
error
Runtime
both

Related errors

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Source: MDN Web Docs. Data fetched 2026-09-25T01:48:37.273Z.