Regular Expressions 101

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/
(\S+.\n)\n(?=Contact)
/
gm
1st Capturing Group
(\S+.\n)
\S
matches any non-whitespace character (equivalent to [^\r\n\t\f\v ])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
. matches any character (except for line terminators)
\n matches a line-feed (newline) character (ASCII 10)
\n matches a line-feed (newline) character (ASCII 10)
Positive Lookahead
(?=Contact)
Assert that the Regex below matches
Contact
matches the characters Contact literally (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String