Chrome Version: 67.0.3396.62 (Official Build) (64-bit)Revision babbbb5b433370f9a7feeb9f98a57599ad1c4676-refs/branch-heads/3396@{#702}
OS: Mac(10.12.6, 10.13.1, 10.13.5).

What steps will reproduce the problem?
1. Launch chrome and click on ‘Cast’ option from wrench menu to open Cast overlay.
2. Now once press ‘Tab’ key from keyboard and observe the focus.

Actual: Focus doesn’t seen on ‘LEARN MORE’ link and focus is lost.
Expected: Focus should seen on ‘LEARN MORE’ link on pressing ‘Tab’ key.

This is a Mac specific regression issue, broken in M-67 series, below is manual regression range.

Good build: 67.0.3378.0 (Revision: 544932)
Bad build: 67.0.3379.0 (Revision: 545318)

You are probably looking for a change made after 545257 (known good), but no later than 545258 (first known bad).
CHANGELOG URL:
The script might not always return single CL as suspect as some perf builds might get missing due to failure.
  https://chromium.googlesource.com/chromium/src/+log/0ace60f0bda35d4788e12314314758465ccf70f5..e09df9251bdc1f717aa76df1629a04143971a15e

Suspecting: https://chromium.googlesource.com/chromium/src/+/e09df9251bdc1f717aa76df1629a04143971a15e

@ellyjones: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

NOTE: 
1. This issue is not reproducible on Win(7,8,8.1,10) & Linux (14.04 LTS) OS.
2. This issue is also reproducible on Beta build # 67.0.3396.56 and Dev build # 68.0.3438.3 and Canary build # 69.0.3444.0

Kindly review the attached screen-cast for reference.

Thank you.
 

Deleted: Actual behavior.mov 4.9 MB

	Actual behavior.mov 4.9 MB View Download

Deleted: Expected behavior.mov 3.1 MB

	Expected behavior.mov 3.1 MB View Download