Network Diagnostics - bring them back, PLZ

Being a MMO game, EVE Online relies heavy on Network conditions !
On game-play issues, Network conditions are the first thing to check.
And EVE software is far from glitch-free or issue-free state ! :-[

These are still present, but moved to the launcher icon in the Notification Area of the various OSes (top menu E icon in macOS, start menu notification area E icon in Windows, as far as I know). Click on that icon and you should get the options for network diagnostics, profile settings copying, and a few other things that used to be accessed from the launcher window itself.