Highlight local PDF files

Why file:// PDFs cannot open in the extension, how to upload them to the dashboard, and what happens to existing local highlights.

The extension cannot read PDFs opened directly from your computer (file:// URLs). Upload the file to the ZetaMarker dashboard to highlight and sync it.

Why local PDFs need upload

Browsers block extensions from accessing arbitrary files on disk for security. When you open a local PDF, ZetaMarker shows an upload prompt instead of the PDF viewer:

Upload this PDF in ZetaMarker

The extension does not open file:// PDFs inline.

Upload from the extension prompt

Open a local PDF — the upload prompt appears.
Click Open ZetaMarker to upload.
Sign in to the dashboard if prompted.
The Upload PDF dialog opens — select the same file shown in the prompt.
After upload, open the PDF in the dashboard viewer to highlight and sync.

The prompt shows the filename so you pick the correct file. Use Copy file path if you need to locate it in your file manager.

Upload from the dashboard

Sign in at app.zetamarker.com.
Click Upload PDF in the header or pages library.
Drag and drop or browse for your .pdf file.
Optionally check Open automatically after upload.

See Upload PDFs to the cloud for size limits and storage.

What about existing local highlights?

Note: Highlights you saved only for a local file in the browser are not transferred automatically when you upload. You may need to re-highlight after upload, or export/copy from the extension sidebar before uploading.

Legacy local pages in the dashboard

If a page shows "This page was a local file on your computer", upload the PDF to enable highlighting and cloud sync in the dashboard viewer.

Deep links

These URLs open the upload flow after login:

/app?upload=pdf
/app?zm_source=local-pdf-prompt

Highlight PDFs in the extension — online PDFs only
View PDFs in the dashboard
Upload PDFs to the cloud