As code evolves, as we find new and better ways to solve things, we sometimes broke all behaviors we had from the back.
Those days of bug fixing were really great as progress, and some areas that we still fixed were to make solver that even is rewritten heavily under the hood, to get things right regarding look&feel, to have well positioned edge continuation and parallelism.
A strange bug was regarding as is changed a rotate in property grid, and you wanted to set it back using Undo, you will have to write it twice. The cause was because by mistake a new layer information was reported as added in an intermediary step, and of course that it was wrong.
You will get better messages when errors occur, mostly on rectangle tools area.
Based on those most likely tomorrow we will make a release that will be both snappy, innovative and less prone to errors.