garrytan/gstack · error · Error

load-html: file does not appear to be HTML. Expected .html/.

Error message

load-html: file does not appear to be HTML. Expected .html/.htm/.xhtml/.svg, got ${ext || '(no extension)'}. Rename the file if it's really HTML.

What it means

Error "load-html: file does not appear to be HTML. Expected .html/.htm/.xhtml/.svg, got ${ext || '(no extension)'}. Rename the file if it's really HTML." thrown in garrytan/gstack.

Source

Thrown at browse/src/write-commands.ts:255

            'Raise with GSTACK_BROWSE_MAX_HTML_BYTES=<N>.'
          );
        }
        const peek = fromFilePayload.html.trimStart();
        if (!/^<[a-zA-Z!?]/.test(peek)) {
          throw new Error('load-html: --from-file html does not start with a valid markup opener');
        }
        const finalWaitUntil = fromFilePayload.waitUntil ?? waitUntil;
        await session.setTabContent(fromFilePayload.html, { waitUntil: finalWaitUntil });
        return `Loaded HTML: (inline from --from-file, ${fromFilePayload.html.length} chars)`;
      }

      if (!filePath) throw new Error('Usage: browse load-html <file> [--wait-until load|domcontentloaded|networkidle] [--tab-id <N>]  |  load-html --from-file <payload.json> [--tab-id <N>]');

      // Extension allowlist
      const ALLOWED_EXT = ['.html', '.htm', '.xhtml', '.svg'];
      const ext = path.extname(filePath).toLowerCase();
      if (!ALLOWED_EXT.includes(ext)) {
        throw new Error(
          `load-html: file does not appear to be HTML. Expected .html/.htm/.xhtml/.svg, got ${ext || '(no extension)'}. Rename the file if it's really HTML.`
        );
      }

      const absolutePath = path.resolve(filePath);

      // Safe-dirs check (reuses canonical read-side policy)
      try {
        validateReadPath(absolutePath);
      } catch (e: any) {
        throw new Error(
          `load-html: ${absolutePath} must be under ${SAFE_DIRECTORIES.join(' or ')} (security policy). Copy the file into the project tree or /tmp first.`
        );
      }

      // stat check — reject non-file targets with actionable error
      let stat: fs.Stats;
      try {

View on GitHub (pinned to 94993f7401)

When it happens

Trigger: Thrown at browse/src/write-commands.ts:255 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of garrytan/gstack@94993f7401 (2026-08-12). Data as JSON: /api/errors/91b6b90649e192a4. Report an issue: GitHub.