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Format of HTTP response header names and values

The name of the HTTP response header you want to set or remove can only contain:

• Alphanumeric characters: a-z, A-Z, and 0-9
• The following special characters: - and _

The value of the HTTP response header you want to set can only contain:

• Alphanumeric characters: a-z, A-Z, and 0-9
• The following special characters: _ :;.,\/"'?!(){}[]@<>=-+*#$&`|~^%

The length of the HTTP response header can be a maximum of 4 KB (~4,096 characters).