What is the opinion of Irish nationalists on COVID-related border checks?
In Why is having border controls in Ireland so problematic for Irish nationalists? and What is the evidence that customs checks in Northern Ireland are going to result in violence? it was explained that Irish nationalists view Ireland as a single country and would use violence in case any sort of border control measures would be introduced. However it seems that at least some border controls were indeed in place during the pandemic, with people turned away when crossing the border for "non-essential" reasons.
Did any Irish nationalist organizations express their opinion on COVID-related checks between the south and the northern parts of the island?