Release 4.223.1

The menu keeps its search field and tabs (the owner, 11-12, two phone screenshots: "the gui gets messed up and loses its tabs", "Missing top tabs").

• What went wrong:
  • 4.223.0's slow light behind the menu is drawn 20% past the panel's edges, and the panel was overflow: hidden.
  • A hidden-overflow box is still a scroll container, so a focus or a scroll into view inside the menu scrolled the whole panel up: the field and the tabs left the screen, with an empty band at the bottom.
• The fix: the panel now clips (overflow: clip is never a scroll container), and any scroll an older engine gives it anyway is put back at once.
• "Your own AI" keeps its name on one line; its sentence takes the wrap.
• New test menu-panel-still-chrome: at 390 and 1280 px, a focus deep in the site list moves the list, never the panel.