React schedule Pro (trial) > Left pane's columns stop being scrollable with computer's pad when using Parent100Pct

When there are more than 2 columns on the left pane and has `heightSpec = Parent100Pct`, why does the left pane's columns stop being scrollable with computer’s scrollpad as soon as the resources’ elements reaches the bottom of the list?

This is current configuration.

<div style={{
        height: '100%',
        display: 'flex',
        flexDirection: 'column',
        overflow: 'hidden',
 }}>
 <DayPilotScheduler
   heightSpec={'Parent100Pct'}
   rowHeaderWidthAutoFitShrink={false}
   rowHeaderWidthAutoFit={false}   
   treeEnabled,
   rowHeaderScrolling,
   rowHeaderColumnsResizable,
   rowHeaderColumnsMergeParents={false}
   rowHeaderWidth: 410, // hard-coded to sum of 2 columns for now
   rowHeaderColumns={[
    { text: "", display: 'info', width: 310, nonresizable: true },
    { text: "Another Column", display: 'another', width: 100, nonresizable: true },
   ]},
   rowMinHeight: 100
 />
</div>

The horizontal scrollbar at the bottom is still visible on hover, but i can only move it using the mouse, but not computer’s scrollpad.