How to disable dock panel resizing on mac?

Question

macOS

When I select the icons in the dock on a Mac, it happens from time to time that I either stretch it or shrink it. Can you suggest two things:

1) What are the actions in which I resize it?
2) How to turn it off?

Answer 1

Resizes when you pull the separator (such a dash).
Disable:

defaults write com.apple.dock size-immutable -bool true; killall Dock

Turn back on:

defaults write com.apple.dock size-immutable -bool false; killall Dock