The same happens in the Omnibox Result List.

Deleted: screencast_2.mov 778 KB

screencast_2.mov 778 KB Download

Here is the Regression Range for this bug: https://chromium.googlesource.com/chromium/src/+log/92466de58f6060945cea3c8cef01302c5e4eec3c..f5345de13668f0176b11126a7ae391dad5b4ad0f

Not sure which one of the changes could cause this.

Thanks for the bisect, Mehmet. It's probably due to changing to the 10.12 SDK:

https://chromium.googlesource.com/chromium/src/+/f5345de13668f0176b11126a7ae391dad5b4ad0f

Note to self: investigate drawInteriorWithFrame chrome/browser/ui/cocoa/location_bar/autocomplete_text_field_cell.mm 

Here's what allowsDefaultTighteningForTruncation is supposed to look like, FWIW.

Deleted: allowsDefaultTighteningForTruncation.mp4 824 KB

	allowsDefaultTighteningForTruncation.mp4 824 KB View Download

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/caa85826fea208a0194983913284d0107146c363

commit caa85826fea208a0194983913284d0107146c363
Author: Erik Chen <erikchen@chromium.org>
Date: Tue Aug 15 23:05:20 2017

mac: Prevent changes to omnibox text spacing during truncation.

When Chrome is built against a 10.11+ SDK, and run on 10.11+, the
allowsDefaultTighteningForTruncation property of NSParagraphStyle defaults to
YES for strings passed to the omnibox. When resizing a Chrome window, this
causes a jarring, but slight, change to the kerning of the omnibox text.

Bug:  754654 
Change-Id: I119a3ba7dad950ee09c75e7f863c387dfd8802e2
Reviewed-on: https://chromium-review.googlesource.com/616166
Commit-Queue: Erik Chen <erikchen@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#494593}
[modify] https://crrev.com/caa85826fea208a0194983913284d0107146c363/chrome/browser/ui/cocoa/omnibox/omnibox_view_mac.mm

Tested on Chrome #62.0.3187.0 and noticed the following observations on Mac 10.12.6:

1. When width of the Window is reduced and increased, distance between the letters seems to be consistent within the omni-box.
2. When width of the Window is reduced and increased, distance between the letters seems to vary in the omni-box results.

Attached is the screencast for reference.

@erikchen -- Could you please look into the issue and confirm whether the Observation #2 is expected or not.

Thanks.

Deleted: 754654.mov 6.8 MB

754654.mov 6.8 MB Download

I see. The same problem occurs to the omnibox autocomplete results.

Updating the summary of the bug.

Your bug is tagged as Release block Stable. 

M62 is branching soon and we will be taking only CRITICAL merges. Please plan accordingly.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5db2b77ad8e5142c4efaefbeefefda34bee2e3f2

commit 5db2b77ad8e5142c4efaefbeefefda34bee2e3f2
Author: Erik Chen <erikchen@chromium.org>
Date: Mon Aug 21 23:57:09 2017

Fix omnibox text tightening for URL suggestions.

Text tightening must be disabled, because it doesn't work well in the omnibox.

Bug:  754654 
Change-Id: I94739c151627e335c22e44d58cd03dc0a82f478d
Reviewed-on: https://chromium-review.googlesource.com/624939
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#496131}
[modify] https://crrev.com/5db2b77ad8e5142c4efaefbeefefda34bee2e3f2/chrome/browser/ui/cocoa/omnibox/omnibox_popup_cell.mm

Verified the CL from C#13 on Mac OS 10.12.6 using chrome version: 62.0.3202.9 and didn't observe any text tightening of URL suggestion when browser was resized. Attached is the screen-cast of the same. Adding the verified label.

Deleted: 754654.webm 5.0 MB

	754654.webm 5.0 MB View Download

erikchen@: I can't reproduce this issue any longer after your fix from comment 13 has been landed. Can we close this report or are you still working on a further CL? Thanks :-)

Removing 'RB-Stable' as per c#14.