Comment by roryokane

Even if you don’t use p4merge, you can set Git’s merge.conflictStyle config to "diff3" or "zdiff3" (https://git-scm.com/docs/git-config#Documentation/git-config...). If you do that, Git’s conflict markers show the base version as well:

  <<<<<<< left
  ||||||| base
  def calculate(x):
      a = x * 2
      b = a + 1
      return b
  =======
  def calculate(x):
      a = x * 2
      logger.debug(f"a={a}")
      b = a + 1
      return b
  >>>>>>> right

With this configuration, a developer reading the raw conflict markers could infer the same information provided by Manyana’s conflict markers: that the right side added the logging line.