Caused by7a943428deLooking at history, e.g.575ade22d4or prior, it seems the "fallthrough" [related compiler warning was removed in7a943428de] was actually intended in the case of `VPAINT_TOOL_AVERAGE`. So first, the average color is calculated and after that regular drawing should happen with that color. Now make this more clear by calling both `calculate_average_color` as well as `vpaint_do_draw` before breaking. Pull Request: https://projects.blender.org/blender/blender/pulls/109971