Sebastien what Chrome version did you notice this on?

59.0.3041.0

woohoo I love one liners https://codereview.chromium.org/2766773002

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c6359868104299cc1eb5fe2700a792d52ecaac6c

commit c6359868104299cc1eb5fe2700a792d52ecaac6c
Author: estade <estade@chromium.org>
Date: Tue Mar 21 18:53:33 2017

Fix Views overlay scrollbar border stroke.

Using a square end cap instead of "butt" makes the stroke extend by a
half stroke width (0.5dp or 1px @2x) at the ends.

BUG= 702744 

Review-Url: https://codereview.chromium.org/2766773002
Cr-Commit-Position: refs/heads/master@{#458493}

[modify] https://crrev.com/c6359868104299cc1eb5fe2700a792d52ecaac6c/ui/views/controls/scrollbar/overlay_scroll_bar.cc

Your change meets the bar and is auto-approved for M58. Please go ahead and merge the CL to branch 3029 manually. Please contact milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), bhthompson@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/277ab19519d29af451139a650fae93da179cc2a0

commit 277ab19519d29af451139a650fae93da179cc2a0
Author: Evan Stade <estade@chromium.org>
Date: Wed Mar 22 22:46:17 2017

Fix Views overlay scrollbar border stroke.

Using a square end cap instead of "butt" makes the stroke extend by a
half stroke width (0.5dp or 1px @2x) at the ends.

BUG= 702744 

Review-Url: https://codereview.chromium.org/2766773002
Cr-Commit-Position: refs/heads/master@{#458493}
(cherry picked from commit c6359868104299cc1eb5fe2700a792d52ecaac6c)

Review-Url: https://codereview.chromium.org/2767283002 .
Cr-Commit-Position: refs/branch-heads/3029@{#373}
Cr-Branched-From: 939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}

[modify] https://crrev.com/277ab19519d29af451139a650fae93da179cc2a0/ui/views/controls/scrollbar/overlay_scroll_bar.cc

There is still some gap between the progress bar line and the top of scrollbar.

Attached screenshot from TOT 9534.0.0, 60.0.3092.0 elm

Reopening bug. Please close if this is WAI.

Deleted: Screenshot 2017-05-09 at 12.15.56.png 9.5 KB

	Screenshot 2017-05-09 at 12.15.56.png 9.5 KB View Download

I think that's because the scrollbar thumb has a white outline.

Thanks estade@

9534.0.0, 60.0.3092.0