Usually the React event system fully respects and follows the way events work in the actual browser DOM.
But with focus and blur this is different. In React, both of these events are bubbled up the tree until they are handled. This is a conscious decision, and even makes it possible to sanely implement alternatives for Focus Outside.
In accessible applications you want to keep the CSS focus outline intact for all elements that can receive focus. But here this bubbling can cause some unexpected side effects.
The input below sits in a focusable container: a div that has been given tabIndex="-1" because we may want to set focus to it later via code. Click on the label below to see the side effect:
These kind of side effects could tempt you to remove the focus outline from elements that should actually have this.
This is where the FocusCatcher component can help you.
Simply wrap clickable content in the FocusCatcher component and it will act as a boundary that catches and handles the bubbled focus event:
Here is the same example as above, but with the FocusCatcher component introduced: