Line string editing by selection vertex

Hi

I have a problem with editing line string by selection vertex.

When I edit line string on one computer it's work correctly. 

link for work correctly -

But I chanced something on the second computer, and when I try editing line string on this computer, it's work different. And I don't know where is the problem. 

link with the problem -

Can someone help me, please.

Thank you

Michal