You may have noticed in Chrome and Safari that scrollbars do not display when you don't have an external mouse and/or keyboard plugged in. This is a feature of Mac OS. If you want the scrollbars to display all the time, follow these steps:
1. Open System Preferences by clicking the System Preferences icon in the launch bar or by clicking the Apple menu and selecting System Preferences.
2. Click into “General.”
3. Under “Show Scroll Bars” select “Always.”
4. Changes are saved automatically, so you can close System Preferences.