This page opens on the laptop drawing because that is the shape of a MacBook keyboard: a function row or Touch Bar area, the main block, and the arrows, with no number pad. The keycap labels say Cmd and Opt instead of Win and Alt. Those words are only labels. The browser still reports the left Command key as MetaLeft and the left Option key as AltLeft. Switching the drawing to Full, TKL, or 60 percent keeps the Mac labels, so a full-size Magic Keyboard can be checked without the names flipping back to Windows. The laptop tester is the same shape with PC labels, if that is what is printed on the caps in front of you.
Several Mac keys never become a keydown. The globe key, fn, brightness, Mission Control, and the emoji picker are often consumed by macOS. A quiet readout is the normal result, not a broken switch. Confirm in TextEdit: if the key does nothing there either, then suspect the switch or the setting that disables it. Newer MacBooks let you change the globe key in System Settings so that it sends a function key. Until it does, this page cannot light it. On older MacBook Pro models the Touch Bar is the same story. Brightness painted on the bar is not F1 unless macOS is set to send function keys. When it does send F1, the function-row button lights.
Option is a dead key. Option+e, then a vowel, is how many accents are typed. The first press may show the key as Dead, or a combining mark, with code AltLeft still held and the letter code arriving after. That is the keyboard doing what macOS asked. It is not a stuck tester. Command is the other trap. Command+R reloads the browser, Command+W closes the tab, and other combinations are taken before you can watch the letter. Test a letter on its own. This page stops Space, the arrows, and Tab from scrolling while it is focused. It does not try to take Command away from the browser.
The code is the useful half of the readout when the character is not. Option changes key into a special character while code stays on the physical key, KeyA or whichever letter you pressed. That split is what you quote if a key works in one layout and not another. keyCode is the old number. A stuck key that stays in the held list after you release it is often a missed key-up because the window lost focus. Click the page and tap the key. If it stays down in a second browser, the switch is closed.
A 60 percent board plugged into a Mac is still a 60 percent board. Open the 60 percent tester when you want Escape on the number row and no arrows in the drawing. Come back here when you care about Command, Option, and the keys macOS keeps. Nothing you press is uploaded. There is no account.