In Yellowfin 7.1, the scroll bar for dashboard portlets onmulti-charts were disabled.
In Yellowfin 7.2 + we enabled the scrolls bars.
If you want to disable the scroll bars in 7.2 + you will need to add the following code snippet to the dashboard.css file.
NOTE: Please only modify a copy of the dashboard.css file, do not update and save the original.
You can then save this .css into the yellowfin\appserver\webapps\root\customcss\ folder and restart YF for the changes to take affect.
An example .css (renamed to .txt) with the change has been attached.