This page demonstrates the reported path for a text input with a datalist. The important part is that the pointer is already over where a suggestion will appear before the popup is opened again.
If the browser has the bug, the first click on an option under the stationary pointer may be ignored until the pointer crosses an option boundary.
1. Click the input and type "i" so datalist suggestions appear.
2. Press Escape to close the popup.
3. Move the pointer to the same screen location where one visible option appeared.
4. Without moving the pointer again, type another character or delete/retype to reopen suggestions.
5. Click the visible option directly under the stationary pointer.The input value should change to the clicked option and this page should log input/change events. The click should not require a prior mouse movement across an option boundary.
On affected builds, the option under the stationary pointer can look hovered, but the first click does not commit it. Moving away and back makes later clicks work.