The Quick Stock Picker Menu displays the same list of files previously accessed from either the File Entry Panel or the File Scan Utility. It allows you to "quick pick" another stock without the need to go back to the parent window. The "Transparency" slider at it's base is for adjusting the dialog's transparency when the mouse is elsewhere on your screen (allowing you to see what's behind the dialog). This slider will also adjust the transparency of the floating Viewport Control Panel.
You can disable the Quick Stock Picker from poppin gup. Press Control-O on your keyboard to bring up the Configuration Options Panel, then open the "Miscellaneous" section, then select "Console Appearance". There you will see an "Enable Quick-Pick Menu" option.
NOTE: When the Quick Stock Picker Menu has been disabled, you can "scroll" your Insider TA graph to the first, previous, next, and last stocks (that are contained in the list) by pressing the Home, PgUp, PgDn, and End keys. This special keypad feature is on only when the Quick Stock Picker Menu has been disabled.