HI Arthur,
I’m afraid I don’t know exactly what you mean (what do you mean with “on the side” and why do you mention ‘clipping’). I was also not able to reproduce this.
The most likely culprits are: ‘double Vertices’, ‘inconsistent Normals’ and having a wrong Selection when trying to Bevel.
So: (in Edit Mode) hit A to Select everything and then M > Merge > By Distance, followed by SHIFT+N. Then try again.
Please let us know if that helped.
