꾹 누르기 & 드래그 테스트 — 스위치 끊김 감지

A hold-and-drag test verifies that a mouse button maintains an unbroken electrical contact for the entire duration of a press. The browser fires `pointerdown` when you press the button and `pointerup` only when you release it. If a `pointerup` event arrives while you are still physically holding the button, the switch has dropped the connection — a clear hardware failure signal.

The drag portion of the test confirms the same behavior under sustained lateral pressure, which is how the issue most often shows up in everyday use: file moves, FPS aim-down-sights, MOBA box-selection, and CAD lasso tools all rely on the button staying down.

Hold and drag dropouts are the second most common micro-switch failure after chatter (double-click). Where chatter produces extra phantom clicks, a dropout produces a missing click — the OS receives a release event that the user never asked for.

In games, a dropped press during ADS aiming or skill channeling can decide a fight. In office work, a dropped drag scatters files across the wrong folder. Identifying the issue early lets you replace the switch before it becomes intermittent enough to ruin productive work.

The hold area listens for `pointerdown` and `pointerup` and uses Pointer Capture so a release outside the element is still detected. A live timer (driven by `requestAnimationFrame`) shows the current hold duration so you can spot a sudden reset visually.

Two release events arriving within 50 ms of each other are flagged as a hold interrupt — a normal user cannot intentionally release and re-press that fast. The drag handle is implemented with the same Pointer Events API; a `pointercancel` mid-drag is logged as a drag interrupt.

Contact cleaner: Open the mouse, drop a small amount of electronics-safe contact cleaner (e.g. DeoxIT D5) into the switch through the actuator slot, then rapidly click the switch 50–100 times. This dislodges oxidation and dust on many older switches.

Switch replacement: For a permanent fix, desolder the failing switch and replace it with a fresh Omron, Kailh, or Huano unit. Switches typically cost $1–3 each. Optical switches (Razer, Bloody) are immune to contact dropouts because they trigger via an LED beam rather than physical contact.

If neither is feasible, file a warranty claim — most premium gaming mice cover switch failures within 2 years.