Is gitlab's triple dot and double dot merge compare files option is reverse from standard git command?

I have a little question on gitlab15.8, could someone help me?

Is gitlab's triple dot and double dot merge compare files option is  reverse from standard git command?

1. init a repo with two branch : main and dev base on commit-sha init

                                 --> main(create a file main-new.txt)
    init (init.txt)--> 
                                 --> dev(create a file dev-new.txt)

2. main add file main-new.txt from base

like this:

3  dev add file dev-new.txt from base

4. get into merge page, and then select different diff option

4.1 triple dot diff(git diff  main...dev)

4.2 double dot diff(git diff  main..dev)

5. but in git shell on local, it show like this:

   

5.1 triple dot diff

5.2 double dot diff