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This contribution presents a new scenario for the origin of the abundance anomalies in globular clusters (GCs). In it, a super-massive star (SMS, >10^3 Msun) forms in the cluster formation process as the result of stellar collisions, triggered by adiabatic cluster contraction due to gas accretion. While collisions grow the SMS, enriched material is released from the SMS via a strong wind and mixes with the inflowing pristine gas and accretes on proto-stars. The enrichment happens fast (~few Myr) and there is only a single generation of stars. The collisions with the SMS act as a dynamical heat source counteracting the contraction, resulting in a super-linear scaling between maximum SMS mass and cluster mass. This self-enrichment scenario (1) reproduces the reported increase of helium spread and the fraction of enriched stars with cluster mass; (2) overcomes the mass-budget problem; (3) allows for the presence of Li. We discuss the various uncertainties and propose tests to validate this idea.