Separate vertical scrolling for the "Releases" and "Parking lot" panes

Short Summary

As an Aha user, I'd like to be able to vertically scroll the Active Releases and Parking Lot Releases panes separately within the Features Board, so that I can clearly see where other releases are when working with long Feature lists.

Detailed summary

When in the Features board, we are presented with two panes: The left pane for Active Releases, and the right pane for Parking Lot Releases. These panes currently allow for separate horizontal scrolling. The Details pane that comes up when you click on a Feature or Release is not being discussed in this Idea and can be considered out of scope.

While these two panes have separate horizontal scrolling, vertical scrolling is "linked" between each other. This means that, if your Features within your Parking Lot Releases are long enough and you scroll down, then you are no longer able to view the Features and Releases within the Active Releases pane. The inverse is true: a long list of Features in your Active Releases will cause you to scroll and no longer be able to see the Releases in the Parking Lot Releases pane.

This is troublesome as it makes Release management between the panes more difficult. Because of the scroll, if you find a Feature in either Pane that you want to move to the other (or even to Releases within the same pane), you are going in "blind" as you cannot tell where the drop targets for your other Releases are. This is bad UX, as it means we may put something in the wrong place, which can cause issues if we do not catch it.

Proposed solution

I propose the following as a preferred solution:

A vertical scrollbar is added to the Active Releases pane within the Features Board
A vertical scrollbar is added to the Parking Lot Releases pane within the Features Board
The current "shared" scrollbar on the Features Board no longer exists

As an alternate solution, I propose the following:

Release headers are "sticky" within each pane and are always visible regardless of the vertical scroll
Drop targets within releases are "sticky" beneath the headers and are always visible when dragging cards regardless of the vertical scroll