Find multiple blank lines in Notepad++ and join the separated text lines
Solution 1:
- Ctrl+H
- Find what:
\R{2,} - Replace with:
LEAVE EMPTY - check Wrap around
- check Regular expression
- Replace all
Explanation:
\R{2,} : 2 or more any kind of linebreak, '\r' or '\n' or '\r\n'
Solution 2:
Depending on what's actually on those lines it might already be sufficient to just Search & Replace \r\n\r\n in extended mode with nothing or maybe a space. If you do have more whitespace characters you could use a regular expression.