[Affected versions]:

• Firefox Nightly 66.0a1, Build ID 20190125095457
• Firefox Dev Edition 66.0b1, Build ID 20190121133415

[Affected Platforms]:

• All Windows
• All Mac
• All Linux

[Steps to reproduce]:

1. Start the browser and open a new tab.
2. Using the keyboard, navigate to the 2nd Top Site's context menu.
3. Press Space and tab through to the last option.
4. Press Tab once more and observe the behavior.

[Expected results]:

• The focus is moved to the 3rd Top Site.

[Actual results]:

• The focus is moved to the 1st Top Site's context menu.

[Regression range]:
21:29.75 INFO: Narrowed inbound regression window from [2809c756, 6479cf44] (3 builds) to [2809c756, 226b130b] (2 builds) (~1 steps left)
21:29.75 INFO: No more inbound revisions, bisection finished.
21:29.75 INFO: Last good revision: 2809c756574d28c25d031eecd41779d3392c44d4
21:29.75 INFO: First bad revision: 226b130b6360f05f7329b3a836177af5bb32fd1d
21:29.75 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=2809c756574d28c25d031eecd41779d3392c44d4&tochange=226b130b6360f05f7329b3a836177af5bb32fd1d

Looks like this was introduced by something in Bug 1519303.

[Notes]:

• The issue is also reproducible on the Recommended by Pocket and Highlight sections.
• Attached a screen recording of the issue.

Bulk change for all regression bugs with status-firefox67 as 'fix-optional' to be marked 'affected' for status-firefox68.

Hi TIm, is this still a P2? (when do you think it will be fixed?) Thanks!

This should be solved by Bug 1554293, which corrects the tab order for topsites and pocket cards. Should be merged soon!

Confirming issue with 66.0a1(20190125095457).
Verified fix 69.0b4 on Windows 10, macOS 10.13.6, Ubuntu 16.04.