To open the Web Console:
- either select "Web Console" from the Web Developer submenu in the Firefox Menu (or Tools menu if you display the menu bar or are on Mac OS X)
- or press the CtrlShiftK (CommandOptionK on OS X) keyboard shortcut.
The Web Console's interface is split into three horizontal sections:
- Toolbar: along the top is a toolbar containing buttons with labels like "Net", "CSS", and "JS". This toolbar is used to filter which messages are displayed
- Message Display Pane: in between the toolbar and the command line, and occupying most of the window, is the space in which the Web Console displays messages