Understanding Different Bars > Sidebars > Changing Display of Sidebars > Hide Mode
In Hide Mode, the sidebar components icons will be hidden from the sidebar in the browser.
In order to bring the icons back, go to View > Sidebar to select components or use shortcut key Alt+4.
From Right-Click Menu
Once the sidebar is in Docking mode, you can right-click on the title bar area to switch the mode.