After using e.g. "Window -> Open inspector in new window" in simplebrowser, since Qt 6.5:

• Left clicking the "»" when the window is too narrow opens the browser context-menu:

• Right clicking a host under "cookies" in the application tab does so too:

• Left clicking the [x] does nothing instead of closing the devtools:

While on Qt 6.4:

• Left clicking the "»" shows a menu with additional tools:

• Right clicking a cookie host shows a "clear" item:

• Clicking the [x] closes devtools.