A laptop keyboard is not a full-size board with the number pad snapped off. The deck people actually have is a function row, the main typing block, and a small arrow cluster. This page opens on that drawing. Insert, Home, End, Page Up, and Page Down are omitted, because most laptops do not have a separate navigation block. The number pad is omitted for the same reason. A large chassis with a real pad is closer to the full drawing on the main tester. Switch to Full and ignore the buttons your deck does not have. A button that lights when you did not press a pad key is a layer on the letters, not a ghost invented by this page.
Fn is the key this test misses on purpose, in the sense that the keyboard often never sends it. Brightness, volume, airplane mode, and the backlight are handled by the laptop before a key code reaches the browser. If F5 dims the screen and the readout stays on the idle line, the browser got nothing. That is expected. Hold Fn and press the same key again. Some machines then send F5, some send a media code the drawing has no button for, and some still send nothing. The readout prints the code either way. A letter that fails here and in a text editor is the switch. A letter that works in the editor and not here means the page was not focused.
The arrow cluster is drawn on its own so a dead arrow is not confused with a 60 percent board, which has no arrows at all. Click the page first. While it is focused, the arrows are kept from scrolling, and Tab is kept from moving focus, so the button can light. If an arrow scrolls the article, the click missed the page. Some laptops print a number pad over the letter keys and turn it on with Fn. Those presses arrive as digit codes and light the number keys in the main block. They are not a separate pad, and the full drawing will not grow one under your hands.
Test the built-in deck with external keyboards unplugged. A wireless dongle left in a port can be the device the browser is reading. If a code never arrives on the laptop and also never arrives on a second machine with the same external board, quote that code. If the failure stays on one USB port of one computer, the deck may be fine. The held list is the rollover check: how many keys this browser still sees down together. Six non-modifier keys is a common ceiling. The page stores nothing.
A 60 percent external board, with Escape on the number row and no function keys, is a different drawing on the 60 percent tester. A MacBook, where the keycaps say Command and Option and the operating system consumes the globe key, is the Mac tester. This page keeps Windows-style labels because that is what most non-Mac laptop keycaps say. The labels are paint. The code underneath is what the browser received.