Nevermind, problem's gone.

Here the current log:

0.002 2019-03-05 14:40:17; Factorio 0.17.6 (build 43339, mac, alpha)
0.003 Operating system: macOS 10.14.3
0.003 Program arguments: "/Applications/factorio.app/Contents/MacOS/factorio"
0.003 Read data path: /Applications/factorio.app/Contents/data
0.003 Write data path ...

Hello,

I encoutered a problem: I tried to install new mods, using the in-game mod portal. After selecting what to download, I get prompted to enter my login cresdencials. After entering them, the mod portal closes and I'm back in the main menu.
I am logged in and/or can log in and out in the ...