Chrome Version       : 65.0.3325.181
OS version               : 10.13.3 (17D102)
Behavior in Safari (if applicable): As expected, reopening existing window
Behavior in Firefox (if applicable): As expected, reopening existing window

What steps will reproduce the problem?
(1) Open chrome and open a new web page A inside of it (e.g. google.com)
(2) Switch to another app using cmd+tab
(3) Open spotlight, type and select Chrome

What is the expected result?
As canonically on Mac OS, the existing chrome window should be brought to foreground

What happens instead?
A new Chrome window is created instead. This is inconsistent with other Mac OS apps' behavior, including Safari and Firefox.