Hi,
since some versions ago (5.1.1ish), Unity editor started to record modifications within prefab assets in the asset’s yaml file. That was usually only done for scene files.
This causes our gameobject assets to grow quite big over time. Worse, it basically ALWAYS causes a merge conflict. The Issue I reported is #711720 and it hasn’t been answered yet.
Could anyone of the devs have a glimpse at this behaviour? It seems in Unity 5.2.0f3, you did some work to make merges more stable but until this is fixed, all this work is basically useless
(ok… its also mostly useless until the UnityUI stops storing all their auto-calculated properties)