Open this page's URL from inside Instagram DM, WhatsApp chat, and a Facebook post (send it to yourself) — not only in Chrome/Safari. Tap each technique, observe what opens, hit Back, repeat. The log survives back-navigation.
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How to read results: for scheme/intent buttons — "left page" ≈ app opened ✅, "no effect" = technique failed ❌. For plain https buttons the page always navigates; note manually whether the app or the browser opened, and whether it landed on the product page.