Previous active tab flicker when navigating the top menu, Navigation sometimes disabled when Webview was last focused

When focusing a tab inside the main panel and then - navigating between the tabs in the top panel - The focused tab inside the main panel flicker, Before menu closes - the previous-focused-tab getting focus even though the user is still on the menu bar - When navigating by keyboard arrows and the previous-focused-tab was a Webview - sometimes the focus not return back to the menu (because focusing on the webview iframe) so navigation is disabled.

Bug Description:

Steps to Reproduce:

For the flicker issue:

1. Focus on a file
2. Click on any tab inside the top menu
3. Navigate between the menu tabs (by mouse/ keyboard)

For the IFrame issue:

1. Open a webview
2. Click on any tab in the top menu
3. Navigate between the menu tabs by keyboard

This is how it flicker:

It happens because there's code for restoring the focus before the menu closes, When navigating on menu - the tab first closes - so previous-focused-tab inside main panel is focused and only then - the next selected tab is opened...

Additional Information

• Operating System: Windows
• Theia Version: Master