OnUnhover being called when it shouldn't

I'm not happy with the builtin tooltip for the polar chart, so I'm attempting to make my own, however I'm having issues with it hiding as soon as it should show, and form what I can tell this is because it's running OnUnhover on every redraw (while the cursor is anywhere near the chart)

I've attempted to set up a simple example here
https://codepen.io/tim-logan/pen/qBqOeMZ?editors=1010

Line 72/73 can be flipped in/out with comments to see the result either in console or directly on the plot.

I may just be doing something wrong, but it looks like a bug to me :)

從連結的 CodePen 重現開始，尤其關注第 72/73 行，並追蹤當游標停留在圖表附近時，極座標圖重繪會在何時觸發 OnUnhover。完成的標準是：自訂 tooltip 在重繪期間保持可見，且只有當指標實際離開相關圖表元素時才執行 OnUnhover。