Unable to get it working for file:/// in zen-browser

[americanjeff]

Was able to install the firefox add-on in zen-browser but even after following all the firefox related post-install steps I have not gotten to to render the markdown. file:///path/to/doc.md shows the plain text version. Happy to help debug this and update the doc if you're interested.

[LouisLau-art]

Same issue here, with some extra diagnostics that might help narrow it down.

Environment

• Extension: Markdown Viewer 5.2.2 from AMO (markdown-viewer@outofindex.com), active, not disabled
• Browser: Zen Browser 1.21.15b (Gecko 154), pacman install
• OS: Arch Linux x86_64

Verified on my side

• about:addons → Permissions → file access is ON (internal:fileSchemeAllowed granted in extension-preferences.json)
• Extension sync storage: origins["file://"] enabled (header + path match, .md regex matches), raw: false, compiler markdown-it
• Manifest has file:///* host permission; no conflicting text/markdown download handler
• Opened via Ctrl+O / drag-and-drop as file:///...test.md (not via system file association)
• Refreshing the tab, reopening the file, and fully restarting the browser all make no difference — the page stays as the built-in plain-text <pre> view, content script never appears to inject

Control case: a different markdown reader extension from AMO renders the same file fine in the same Zen profile, so general file:// access in this profile works — this looks specific to how Markdown Viewer detects/injects on current Gecko.

Happy to test a debug build or pull console logs if you tell me what to look for.