D3 Tree Chart Collapsible
Access the charts from

 Ctrl key and the mouse scroll wheel to zoom in
 Right Click to display the context menu
 Resize the chart window by placing your mouse on the edge or corner of the window.
- until the resize arrow appears ↔ ↕ 

- then hold the left mouse button down and drag.

Please use the following shortcuts, (these are also listed on the popup menu)
Shortcut keys  Menu Title  Description
dDownload  Download
eEdit  Edit
eExport  Export
wFit To Window  Fit_To_Window
hHelp  Help
oOverLay  Over Lay
pPreferences  Preferences
rRefresh  Refresh

(Click on the image to enlarge)