meld

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

meld

meld path/to/file_1 path/to/file_2

meld path/to/directory_1 path/to/directory_2

meld path/to/file_1 path/to/file_2 path/to/file_3

meld --newtab path/to/file_1 path/to/file_2

meld --diff path/to/file_1 path/to/file_2 --diff path/to/file_3 path/to/file_4