Desktop preview pane serves stale HTML — doesn't refresh on Reload after the file changes

What happened

In the Claude Code desktop app, the Launch preview pane renders a static local .html file once and then serves a stale snapshot. After the underlying file is changed on disk, pressing the Reload button in the preview pane does not update the rendered content — it keeps showing the original version. The file on disk was confirmed updated (both <title> and body changed). Only fully closing and re-launching the preview — or pointing the preview at a brand-new filename — shows the new content.

Steps to reproduce

1. Create review.html and open it via Launch preview in the desktop app — it renders correctly.
2. Modify review.html on disk (e.g., change the <title> and replace the page body).
3. Click the Reload/refresh control in the preview pane.
4. Expected: the preview reflects the updated file.
5. Actual: the preview still shows the original content. Confirmed by re-reading the file that disk content was updated.

Notes

• No dev server is involved — this is a plain static .html.
• Reload does not bust the cache; it behaves as if the webview cached the initial parse/render and the reload re-serves the cached resource (looks like missing no-cache headers / no cache-busting on reload).
• Workaround: open the file directly in an external browser, or write to a new filename each time (a never-before-launched path always renders fresh).

Impact

Iterating on generated HTML (e.g., an image-review/approval page that Claude regenerates) is confusing — it looks like edits didn't save, when they actually did.

Environment

• Claude Code: 2.1.162
• App: Claude Code desktop
• OS: Windows 11, ARM64 (Snapdragon X Plus)