will be added before the new trailer.
Existing trailers are extracted from the input message by looking for
-a group of one or more lines that (i) are all trailers, or (ii) contains at
+a group of one or more lines that (i) is all trailers, or (ii) contains at
least one Git-generated or user-configured trailer and consists of at
least 25% trailers.
The group must be preceded by one or more empty (or whitespace-only) lines.