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There was an error published in Development 138, 861-871.
In Fig. S5 in the supplementary material, in Stage 5 of Protocol 2 and Protocol 2 + Act, the medium should be SFD, not DMEM. In Fig. S10 in the supplementary material, in Stage 5 the medium should be SFD, not DMEM, and in the timeline d5 should be d3.
The authors apologise to readers for this mistake.
