Liferea ignores the --mainwindow-state= parameter

I want liferea to startup when gnome starts. I added the following command to the Startup Programs in System --> Preferences --> Sessions

"liferea --mainwindow-state=hidden"

after reading the man page. However, still on startup, the main liferea window pops up, maximized. This is very very disrupting, and not the normal behaviour.

Even when I try the same command from gnome-terminal, the results are the same, i.e. the liferea window pops up maximized.

Thanks!