Thunderbird proofreading

Email proofreading that stays under your control.

Viska Brev proofreads Swedish and English drafts directly in Thunderbird. Run locally with Ollama, or use OpenRouter with your own API key when you want cloud models.

Download .xpi Install steps

Latest build: 0.3.1 for Thunderbird 128+.

Ollama local mode OpenRouter cloud mode Diff preview GPL-3.0-only

Why Viska Brev

Clean up the draft, not your voice.

The extension opens a proofreading panel in Thunderbird's compose window. Choose spelling, grammar or expand mode, review the green/red diff, then accept only when the result is right. Quoted mail and signatures are left alone.

Spelling Grammar Expand Language auto-detect Protected quotes Protected signatures

Viska Brev plugin in Thunderbird compose window: real diff highlighting with red deletions and green insertions, change count, Ersätt and Förkasta buttons.

Download

Install from the XPI file.

Viska Brev is self-hosted for now. Thunderbird can install unsigned extensions from a local file, so the XPI works without Add-ons store publishing.

viska-brev-latest.xpi viska-brev-0.3.1.xpi

Version: 0.3.1
Size: 49 KB
Requires: Thunderbird 128+
SHA256: 465bb31ca3fe758d728dabf757d788d8b53e9aad888e0b2a7127d46a9f92e310

Install

Add it to Thunderbird manually.

Verify the checksum in downloads/SHA256SUMS if needed. For local AI, Ollama keeps the draft text on your computer. For cloud proofreading, paste your OpenRouter key in the extension settings.

1. Download viska-brev-latest.xpi
2. Thunderbird -> Tools -> Add-ons and Themes
3. Gear menu -> Install Add-on From File
4. Select the .xpi file

Local AI:
ollama pull gemma3

Cloud AI:
Add an OpenRouter API key in settings

Coming next

The Viska bridge.

A later Viska Brev version is planned to add a microphone button that talks to the Viska desktop app over D-Bus, so dictation and proofreading become one flow inside Thunderbird.