moderated Re: dropbox.com webpage
In addition to Mr. Griffith's mentioning of Windows Key+B to throw focus into the notification area (often referred to as the system tray or task tray) section of the taskbar, Microsoft is one of the best companies I know of when it comes to documenting keyboard shortcuts and making finding what you need easy.
Windows Keyboard Shortcuts Page: https://support.microsoft.com/en-us/help/12445/windows-keyboard-shortcuts
Once opened, defaults to Windows 10 but there is a dropdown at the top that lets you change the Windows version should you need to.
Activate the Show All link near the top of the page so that every keyboard shortcut is on display and then search using whatever keyword is appropriate to what you're looking for.
Brian - Windows 10 Pro, 64-Bit, Version 2004, Build 19041
The purpose of education is not to validate ignorance but to overcome it.