filter Subject VS subject

There should be no difference - mail header names should be treated case-insensitively.
 
There should be no difference - mail header names should be treated case-insensitively.
I asked the wrong question.
Example:
When a new email is arrived and his the subject field is in lower case(email subject=subject). It will be captured by my filter, which will be Match field=> "Subject = prol.klin." only ?

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yes it should match - no matter how 'subject' is written in the mail header