Spikes and protruding lines appear around the outer edges of polygons due to the combination of the outline width and cartographic line with negative offset settings.
The reported issue, as it is described, cannot be reproduced within the currently released build.
対処法
Workaround 1: Use the Generalize tool. The tool separates the vertices evenly and prevent protruding lines from appearing.
Workaround 2: Zoom to where the protruding line begins, double-click the polygon to reveal the vertices, and separate the ones that are the closest. This can be done by right-clicking on a vertice to remove it and by right-clicking on a line to add a vertice at another location if needed.