TableView: MouseArea.hoverEnabled ignored if used within headerDelegate; affects tooltips, cursors, mouse enter/exit/hover/move/etc events

I wanted to display tooltips with column titles for the column header cells as the titles are long and get clipped because the column widths are small to save space and only accommodate the data (up to three digits) but failed miserably due to what looks like an improper dispatching of mouse events.

Reproduce:
0. Build the (very simple) desktop application from the sources attached: TableViewHover_sources.7z.
1. Run the app, watch the JS console.
2. Move the mouse slowly all the way across the header row e.g. left to right.
3. Click and hold the header cell in column 0 or 1, drag to another row, release.

Expected:
2: Every time the mouse enters/exits a cell, a onContainsMouseChanged call happens with containsMouse being true/false respectively.
3: The calls to onContainsMouseChanged happen when the mouse pointer crosses cell boundaries.

Actual:
2: No onContainsMouseChanged calls are generated by columns 0 and 1; surprisingly, the space past the last column (a.k.a. "column -1") behaves as those normal columns should have behaved.
3: The calls to onContainsMouseChanged happen when mouse button is pressed/released.