Chrome Version: 69.0.3497.100 (Official Build) (64-bit)
OS: Linux

What steps will reproduce the problem?
(1) Create an empty bookmarks folder and have at least one other folder next to it in the bookmarks bar.
(2) Click to open the empty folder (revealing the "(empty)" message).
(3) Without clicking, move the mouse back and forth horizontally between the empty and non-empty adjacent folder in the bookmarks bar.

What is the expected result?
Each time the mouse moves over the empty folder, a single "(empty)" dummy entry appears.

What happens instead?
Each time the mouse moves over the empty folder, an _additional_ "(empty)" appears. There can be an arbitrary number of such entries added by moving the mouse back and forth. The dummy entry count resets if the bookmark folder dropdowns are dismissed.