Sizing tooltip "container"

I am using fairly wide (pictures) content for tooltips. No problem to adapt the width of the "tooltip text", however I can see a white container that I cannot seem to resize.

When I open the right-most tooltip on screen, the content are not fully visible (it's spilling over the screen to the right).
For a while I had it working as expected (if the content of the tooltip is not visible, it will automatically re-position itself, to the left of the mouse). But I cannot seem to get it to work again.

I reckon this is because resizing the tooltip text is not resizing the underlying "container" -if that makes sense.

Any idea on how to fix that, so that mouse-over content is always visible if it's larger than whatever space is available on the right-side of the screen/navigator window?

Thanks,
amic

Resolved