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# TextDecoder.fatal

The **`fatal`** read-only property of the `TextDecoder` interface is a `Boolean` indicating whether the error mode is fatal.

If the property is `true` then a decoder will throw a `TypeError` if it encounters malformed data while decoding.
If `false` the decoder will substitute the invalid data with the replacement character `U+FFFD` (�).
The value of the property is set in the `TextDecoder()` constructor.

## Value

A `boolean` which will return `true` if the error mode is set to `fatal`.
Otherwise it returns `false`, indicating that the error mode is "replacement".
