dashlet scrollbars missing in 14.0.x

I have some very basic custom Dashlets that we've had since the intelligence pane was first introduced years ago.
Since upgrading from v11 -> v14.x we lost the scroll bars on the side/bottom of these dashlets.

Any suggestions on how to rewrite/correct these?

The dashlets are all similar, with a controller that calls an API (in Sugar or an external resource), takes the results and puts them in a very basic table:
controller:

metadata:

hbs: