Ah, HumbleNoise, I definitely remember that username. Good to see you around again as well.
It's always been possible to roll out a groove clip to any intermediate length, depending on snap settings. If snap isn't enabled or is enabled at a low duration value and/or with a low magnetic strength, the boundary may not snap clearly to the end of the groove. Setting snap duration to Measure, and "Extreme" magnetic strength will make it more obvious when you hit the repeat point even if the colors are obscuring the beveled corners.
I often end up with groove clips that have only a partial repeat at the end (or at the beginning if I roll the start point earlier). Related to this, I like to make groove clips for drum parts have different/odd lengths so that the interplay of repeating patterns in different parts is always evolving throughout an otherwise repetitive groove.