70c723135b
When ToolbarKeyboardNavigator initializes, it sets aria-hidden and adds a focus listener on toolbartabstop elements. This is necessary for proper functionality of toolbar keyboard navigation. However, widgets can be dynamically added by CustomizableUI after ToolbarKeyboardNavigator initializes. The search bar is one such widget and it does contain toolbartabstop elements. We now watch for this and initialize any toolbartabstop elements inside added widgets. Differential Revision: https://phabricator.services.mozilla.com/D62178