Why is zooming out on ctrl?

Question

Keyboard

Windows 8.1 x64 seems to have the latest major updates. Notebook Lenovo G500.
In all browsers (maybe not only, but noticed only in them) there is a zoom out when holding the left ctrl. Not always, but from time to time (sometimes every 5th time, sometimes 10th). Very annoying, because in the browser I usually use ctrl quite often - to open the page in a new tab.
I don't see any pattern at all. It happens in Chrome, and in Firefox, and even in naked Opera Developer (I don’t use it, but I tried it).
Sometimes it reduces from 100% to 90, and sometimes even up to 33%. I don't understand what it depends on either.
Right ctrl did not try, because it is inconvenient.
Occurs almost from the very purchase (about 2 months). I already sin on a hardware marriage.
Scrolling on the touchpad is only 2-finger (that is, there is no zone for a single-finger scroll), I did not notice an accidental two-finger touch behind me.
With what it can be connected, can, who faced?

Answer 1

I understand! This is a glitch in the drivers! The scale decreases with inertial scrolling, when the fingers have already been released, and the scroll continues. Yes, well, I messed up.

Answer 2

Believe it or not, this is not a bug, it's a browser feature. Even in MS Word 2007 and above, you can adjust the zoom by holding the control and turning the mouse wheel. Usually the edge of the touchpad replaces the mouse wheel. And yes, this is a very handy feature.
PS. I would really like to see the faces of people to whom you would bring a laptop for service with this problem))))

Answer 3

It may be due to the fact that when holding CRTL and moving on the touchpad, CRTL + scrolling is simulated, which is actually a zoom change.

Answer 4

In general, Ctrl + Scroll is the standard combination for zooming. Most likely you either have a "soft" scroll on your mouse and you often touch it with the key pressed, or you touch the touchpad on the laptop (or some kind of pickup on it).