[Bug]: Local HTML files open to a blank viewer in T3 Code Desktop

Before submitting

• I searched existing issues and did not find a duplicate.
• I included enough detail to reproduce or investigate the problem.

Area

apps/desktop

Steps to reproduce

1. In T3 Code Desktop, open a project containing a local .html file.
2. In the right-hand workspace file explorer, click the HTML file (reproduced with docs/issues-log-effort.html).
3. Leave the embedded rendered-page view selected.
4. Observe the center viewer pane.
5. Toggle to Show HTML source and confirm that the file contains normal HTML content.
6. Open an adjacent .md file as a comparison; its contents display normally.

Expected behavior

The local HTML document should render in the embedded viewer. If rendering fails, the pane should show an actionable error instead of a blank page.

Actual behavior

The HTML file opens as a completely blank white pane. The embedded document resolves to chrome-error://chromewebdata/ with no visible error or recovery controls.

The HTML source view works and shows the file's contents, and an adjacent Markdown file opens normally, so the failure appears isolated to rendered HTML files in the desktop file viewer.

Related but not an exact duplicate: #7212 concerns a failed floating browser preview; #10935 concerns compressed assets rendering as plain text.

Impact

Major degradation or frequent failure

Version or commit

T3 Code 0.0.40 (Stable)

Environment

macOS; T3 Code Desktop 0.0.40 Stable; local checkout

Logs or stack traces

Embedded viewer document URL: `chrome-error://chromewebdata/`

Screenshots, recordings, or supporting files

No response

Workaround

Toggle Show HTML source to read the file, open it in an external browser, or use a Markdown version instead.

Start in apps/desktop by reproducing the blank viewer with docs/issues-log-effort.html, then inspect the embedded rendered-page view and its Show HTML source toggle. Compare the local HTML path with the working Markdown view and verify that the document renders or presents an actionable error instead of chrome-error://chromewebdata/.