Great question — answering as the UphillTech team:
About thirty seconds after I initiated the bounty, I found the solution. So simple it was difficult... Instead of, e.g.: https://www.instagram.com/p/LetTerS -- simply replace with https://m.instagram.com/p/LeTtErS/ When opened on desktop, Chrome (tested) quickly resolves back to "www." - the phone opens the link in a browser properly (tested on Nexus 5X, Samsung Something).
Full answer by Xodarap777: https://stackoverflow.stackexchange.com/a/51563801 (CC BY-SA 3.0).
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