Review follow-up for the L-shaped header strip:
- _syncTabStripCorner() keeps the plain wrap when the plain strip is
already past --tab-strip-max-height, checked before .tabs-corner goes
on: the float scrolled with the tabs while the toolbar stayed put, so a
scrolled strip put tabs under #headerRight, and a re-render of a
scrolled two-rows strip sized the float from the scrolled frame. The
"- scrollTop" in contentTop is gone (always 0 now).
- A strip just under its max-height that passes it once the float is in
falls back to the plain wrap as well.
- test/tab-strip-corner.browser.test.ts (real Chromium, real header and
styles.css), listed in BROWSER_TEST_GLOBS.
- src/web/CLAUDE.md Tab layouts entry describes the L-shaped classic strip.
