Chrome Version: 73.0.3668.0

What steps will reproduce the problem?
(1) Enable chromevox (ctrl alt z)
(2) Hover mouse over a shelf button until tooltip shows.
(3) Run mouse across the rest of the shelf buttons (tooltips will show for these butons instantly).

Bug:
All of the shelfbutton tooltips announce. This means chromevox will read out every tooltip, which blocks chromevox for quite a while. Can we interrupt the tooltip announcement instead of stacking them?


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