edit mode grab tool doesn't work as expected I thought this would have been a common problem to encounter but I hasn't seen any questions about it being asked.
It may have been me clicking the wrong shortcut but my grab tool doesn't work as expected anymore. Grabbing now extends new edges and forms new vertices. I want the grab tool to work in a way where the very same edges gets extended, whilst displacing the selected vertices. photo included in what I meant. I am able to fix it to make it work as desired, but I kept bumping into the same problem, and I am not sure whether you guys have any advice so I can stop myself from doing it, and waste my time fixing it before moving on with my project :) Thanks for reading!
I believe what happened is that I've been clicking a shortcut accidentally that creates new vertex and edge. But I am still not sure which keyboard button that is
Undesirable effect

Desired effect
Your vertices and edges have been inadvertently set to be split automatically. Find the Options pulldown in the very top-right of the 3D View. Inside of it is the checkbox.

NOTE: If you don't see the Options pulldown at the top right of your screen, it may be that your Tool Settings bar has been disabled. To re-enable it, float your cursor just to the outer edge of any  one of the clickable buttons at the top of your 3D view (such as the buttons for View, Select, Add, etc.), but without your cursor actually touching those buttons. When your cursor changes from a cross to an arrow, right click, and you will get the option to turn on the Tool Settings. Then you will see the Options pulldown. From there you can turn off Split Edges &amp; Faces.