Did you know that there is a popup menu key, that allows you to open the context menu in list views?
Well the GTK default binding is - and on Windows Keyboards the context menu key (usually near to the right of your ey) . As GTK does not handle it as an alias for the 3rd mouse button event each application needs to implement this event for each list view separately :-(
Until now Liferea did not implement this keybinding. Keyboard users will be happy with the upcoming release 1.7.6 which introduces support for this feature based on a patch by Ricardo Cruz.