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# Error: $interpolate:unknarg
Unrecognized MessageFormat extension

    Unsupported keyword “{0}” at line {0}, column {1}. Only “plural” and “select” are currently supported.  Text: “{3}”

## Description

The MessageFormat extensions provided by `ngMessageFormat` are currently limited to "plural" and "select". The extension that you have used is either unsupported or invalid.

For more information about the MessageFormat syntax in interpolation expressions, please refer to MessageFormat extensions section at Angular i18n MessageFormat