Why Is the D Key Not Triggering Keyboard Events in My SvelteKit Game?

Try narrowing it down systematically: run the app on another machine, test a different browser, disable extensions, and compare the current version with the last commit that worked. A binary search through the commit history can quickly identify which change introduced the problem.

Language-input tools or keyboard utilities can also interfere with browser key events, so temporarily disabling those is worth checking if the key works everywhere else.

The commit history may point to the real cause. One of the later changes appears to attach event handlers differently and no longer removes them with `removeEventListener`. That can leave old handlers attached and create unexpected behavior after remounts or reloads.

The D key may just be a red herring. Make sure listeners are registered only once and are cleaned up when the Svelte component is destroyed. Store the handler function reference and remove that exact reference during cleanup.

The missing TypeScript annotations shouldn’t make one physical key stop working. First check whether the event reaches the page at all by running something like `window.addEventListener("keydown", e => console.log(e.key, e.code))` in DevTools and pressing D.

If nothing is logged, temporarily disable Brave extensions, try a private window, and test in another browser such as Firefox or Chrome. Also check whether D works normally in the same tab when typing in DevTools or another input. That will help separate an application problem from a browser or OS-level issue.