The quest of exotic hadrons with multiquark configuration beyond theconventional constituent quark model has been one of central subiects inhadron physics for decades. Among others, the doubly heavy tetraguarkcomposed of two heavy quarks and two light antiquarks attracts significantinterest, since it represents the simplest candidate with explicit multiguarkfeature and is expected to be bound under strong interaction in the heavyquark limit. After decades of joint efforts from both theoreticians andexperimentalists, the first doubly charmed tetraguark