[Affected versions]: - Nightly 59.0a1 [Affected Platforms]: - All Windows - All Linux [Prerequisites]: - Have the latest try build 59.0a1 from (2018-01-05) installed. - Accessibility tab is activated, but not enabled. - Toolbox Options layout is displayed. [Steps to reproduce]: 1. Click on Accessibility tab from the tab strip. 2. Click on the "Enable Accessibility Features" button and observe the way it reacts. 3. Click on the "Disable" button and observe the way it reacts. [Expected result]: 2. The "Enable Accessibility Features" button disappears without delay when the feature is enabled. 3. The "Disable" button disappears without delay when the feature is disabled. [Actual result]: 2. The "Enable Accessibility Features" button is displayed as focused (blue text and borders) for a second. 3. The "Disable" button is displayed as focused (blue text and borders) for a second. [Notes]: - A loading icon is also displayed on the left side of the buttons; - Attached is a screenshot with the issue: