When using :PhpactorGotoDefinition, the jump list seems to have an extra item matching the first line of the destination file. This is a bug I remember having for quite some time, never bothered reporting it until now but it does seem to be related to phpactor because using the native tags-based <C-]> does not produce that bug.

For instance, in doctrine/orm:
vi tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php
44j$bb:clearjumps<CR>:PhpactorGotoDefinition<CR><C-O>:jumps will show the issue