I don’t think it’s a bug, but maybe it can be changed:
When you have multiple military buildings, for example, 2 barracks, and you select both and research a tech (say men-at-arms research) and queue say 5 militias, The result is:
one barrack will research the tech
the other barrack will queue all 5 units
so after the men-at-arms research, the first barracks will be idle and the second barracks will still have like 3 or more units on the queue
Desired behavior: when you have multiple military buildings selected and queue techs and units, the units are lined up in all buildings, including the buildings with tech reserachs queued. As an optimal scenario, calculations would be made to the time needed to research and train all units and techs.