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interactionsRauno

Dropdown Menus on Mousedown

SHOULD

SHOULD: Open dropdown menus on `mousedown`, not `click` — `click` fires on mouseup and adds perceived latency to the press.

Dropdown menus should trigger on mousedown for immediate response, not on click

Bad

Good

Why it matters

The click event fires on mouseup — after the button is released. For dropdown menus that should feel instant, triggering on mousedown removes the perceived delay between pressing and seeing the menu appear.

References

Built by Gleb Stroganov, design engineer at Evil Martians.

The rules come from other people's skills and guidelines — Vercel, Rauno Freiberg, @Ibelick, impeccable, Emil Kowalski, Tailwind, RAMS — each one credited on the Sources page. The work here is extraction and wiring: every rule is pulled into one corpus, given a good and a bad example you can operate, a MUST/SHOULD/NEVER rule an agent can paste, and a link back to where it came from.