"Modify" condition not work with bool value in message?

[Garved]

I try to use a fluent-bit filter "modify" with condition "Key_value_matches"
In docs, this filter are use how: Key_value_matches | STRING:KEY | REGEXP:VALUE | Is true if key KEY exists and its value matches VALUE .
But, in my message, VALUE type is boolean and the filter cannot find a match in the message.
Is it possible to use "MODIFIY" filter with a boolean value type in the "Key_Value_Match" condition?