The issue is not that, Damien, see the overall numbers and count just a few passed test cases from tet results column, thez do not match, seems like this addon just shows the first level of tests, as seen on the image. Which, at least in our case, are test suites (describe in mocha) .
Hm dropping out things is arguable, as a good idea, user might wanna see this for whatever reason, however that does not change the fact that the numbers are wrong in the overview and it seems they just show a number of test suites.