Native browser tooltip for title shows on first keyboard focus in IE/Edge (in addition to Bootstrap's custom tooltip)

IE11 and Microsoft Edge show a native tooltip for focusable elements with a title attribute when focused with the keyboard (while other browsers generally only show the native tooltip when hovering with the mouse). Bootstrap's tooltips blank out the title attribute on when they're focused/hovered, but not fast enough for IE11/Edge not to see them and trigger the native tooltip, meaning that when navigating with the keyboard in IE11/Edge, the first time an element with a tooltip is focused, both the native tooltip and the bootstrap tooltip are shown simultaneously. If the user focuses another element and then returns to this element, no native tooltip is shown (as by that point the title is empty).

(note that in this screenshot, a special red focus outline was forced using a custom stylesheet, for clarity)

Likely solution would be to blank the title out directly when they're initialised, rather than relying on this to happen when they're first focused/hovered.