What happened and steps to replicate:
When in private browsing mode, clearing the last (or only) tab by holding down the tab button and selecting "Close This Tab" leads to a blank UI.
Similarly, when closing the last tab within the tabs menu in private browsing mode and then pressing "Done", the UI flashes a blank UI and suddenly displays the startup in a "janky" manner.
A crash is also present when using the "Close Tabs & Clear Data" functionality in private browsing mode with two or more tabs present.
Attached is the video that demonstrates all of the aforementioned.
The desired functionality would be for the users to not see a "Close This Tab" button when it is the only tab OR to see a "Close This Tab" button but tapping it does nothing (as it is already the last tab).
When closing the last tab within the tabs menu in private browsing mode, it is correct to see the "No Results" screen. However, subsequently, hitting the "Done" button should not oddly flash a blank UI and then immediately display the start page. There should be some sort of animation to more gracefully change.
The browser should not crash when using the "Close Tabs & Clear Data" when there are two or more tabs in private browsing mode.
In short, TL;DR, replicate Safari's handling of private tab management and the action of holding the tab button to clear tab(s) in private browsing mode.
1.3.6 (2) (WebKit 8617.1.17.10.9)
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