/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String line = "<p dir=\"ltr\">Test<br>\nA\naa</p>\nabcd\n<p dir=\"ltr\">Bbb</p>"; 
		System.out.println(line.replaceAll("(?s)((?:<p|\\G(?!\\A))(?:(?!<\\/p>).)*?)[\\n\\r]+", "$1"));
	}
}

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