# Mullvad Browser 16.0a6

- Product: Mullvad Browser (https://whatsnew.fyi/product/mullvad-browser)
- Vendor: Mullvad VPN
- Date: 2026-05-05
- Version: 16.0a6
- Original notes: https://github.com/mullvad/mullvad-browser/releases/tag/16.0a6
- Permalink: https://whatsnew.fyi/product/mullvad-browser/releases/16.0a6
- Labels: Pre-release; Platforms: Desktop

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **changed** — Updated Firefox to 150.0a1
- **changed** — Updated NoScript to 13.6.17.90101984
- **changed** — Updated Mullvad Browser Extension to 0.9.10
- **changed** — Use border radius for letterboxing
- **changed** — Customize the flags for alternate Application Data directories
- **fixed** — Hide the Firefox mascot in about:neterror
- **fixed** — Error in privacy preference initialisation due to missing dataCollectionViewProfilesMultiProfileBackupWarning
- **fixed** — Fontvis is missing Segoe MDL2 Assets on Windows
- **changed** — Disable widget.wayland.fractional-scale.enabled on Linux
- **changed** — Start using LTO for firefox project
- **changed** — Update toolchains for Firefox 150

* All Platforms
   * Updated Firefox to 150.0a1
   * Updated NoScript to 13.6.17.90101984
   * Updated Mullvad Browser Extension to 0.9.10
   * Bug 528: Rebase Mullvad Browser alpha onto 150.0a1 [mullvad-browser]
   * Bug 44402: Re-enable ESLint rule mozilla/no-browser-refs-in-toolkit as an error
   * Bug 44560: Customize the flags for alternate 'Application Data' directories [tor-browser]
   * Bug 44685: Use border radius for letterboxing [tor-browser]
   * Bug 44749: Check search engines parameter replacements [tor-browser]
   * Bug 44828: Remove browser module references from toolkit/modules/ActorManagerParent.sys.mjs [tor-browser]
   * Bug 44832: Hide the Firefox mascot in about:neterror [tor-browser]
   * Bug 44847: Drop letterboxing sidebar rounded corner logic [tor-browser]
   * Bug 44865: Block chrome://*/locale/* to content [tor-browser]
   * Bug 44870: Remove legacy branch from gitlab templates [tor-browser]
   * Bug 44895: Undo the patch for #44772 [tor-browser]
   * Bug 44902: Error in privacy preference initialisation due to missing `dataCollectionViewProfilesMultiProfileBackupWarning` [tor-browser]
   * Bug 31860: Start using LTO for firefox project [tor-browser-build]
 * Windows
   * Bug 44862: Fontvis is missing Segoe MDL2 Assets [tor-browser]
   * Bug 44868: Backport 138c33ea964b2e0a4875aadc39d8a948e0c2aace to 150 to fix Windows builds [tor-browser]
 * Linux
   * Bug 44521: Disable widget.wayland.fractional-scale.enabled [tor-browser]
##### Build System
   * All Platforms
     * Bug 41764: Update toolchains for Firefox 150 [tor-browser-build]
     * Bug 41767: Add jwilde to allowed signer for browser projects [tor-browser-build]
     * Bug 41778: Remove base-browser from protected-branches.py [tor-browser-build]
     * Bug 41780: Create sha256sums-unsigned-build.txt in artifacts/$platform directories [tor-browser-build]
     * Bug 41786: Add comment to rbm.local.conf.example warning about potential recursive loops in tmp_dir definition [tor-browser-build]
     * Bug 40106: Improve error message in case of recursive definition [rbm]
   * Windows
     * Bug 44853: Update target in mozconfig-windows-x86_64 and mozconfig-windows-i686 [tor-browser]
   * macOS
     * Bug 41773: Change the position of -mindepth when creating the dmg [tor-browser-build]