meld

Graphical diffing and merging tool. More information: https://meldmerge.org/.

• Start meld:
  meld
• Compare 2 files:
  meld {{path/to/file_1}} {{path/to/file_2}}
• Compare 2 directories:
  meld {{path/to/directory_1}} {{path/to/directory_2}}
• Compare 3 files:
  meld {{path/to/file_1}} {{path/to/file_2}} {{path/to/file_3}}
• Open a comparison as a new tab in a pre-existing meld instance:
  meld --newtab {{path/to/file_1}} {{path/to/file_2}}
• Compare multiple sets of files:
  meld --diff {{path/to/file_1}} {{path/to/file_2}} --diff {{path/to/file_3}} {{path/to/file_4}}