Affected versions

• 89.0a1(2021-03-28), 87.0;

Affected platforms

• Windows 10, Ubuntu 20;

Steps to reproduce

1. Launch Firefox, access about:url-classifier
   • Proton prefs enabled;
2. Press the TAB key and cycle through the available items in the page;

Expected result / Enhancement suggestion

• checkboxes have spacing between them so that the focus-ring doesn't overlap with the adjacent checkboxes;
• Start searching button is in the same line as the Blocklist button

Actual result

• focus ring touches adjacent checkboxes;
• Start searching button not on the same base-line as the other elements in table;

Regression range

• not a regression;

Additional notes

• attached recording to illustrate the issue.