Firefox 43 arrives with 64-bit version for Windows, new strict blocklist, and tab audio indicators on Android
Emil Protalinski / VentureBeat :
Context & Ripple Effects
Mozilla has been staging this release for most of 2015: it first put a 64-bit Firefox on Windows via Developer Edition back in March, then shipped tracking protection and Android tab audio indicators in Firefox 42 two months ago. Firefox 43 is the point where those parallel tracks converge — the 64-bit Windows build graduates from a developer-only channel to the mainstream release, while the strict blocklist hardens the add-on gating that Firefox 42 began.
First-order effects
- Windows users on Firefox 43 get the stable 64-bit client for the first time, ending the split where only Developer Edition testers ran the wider-memory build.
- Add-on authors now face a stricter blocklist at release time, so extensions that previously squeaked through Firefox 42-era checks risk being disabled for existing users immediately.
Second-order effects
- A stricter blocklist shifts maintenance costs onto the extension ecosystem: developers must keep pace with Mozilla's criteria or lose distribution, thinning out marginal add-ons.
- Shipping the 64-bit build through Developer Edition first sets a template other Firefox features follow — validate on the developer channel, promote to stable — which compresses the gap between experimental and mainstream releases.
Third-order effects
- The 64-bit graduation is a stepping stone in an architecture overhaul that continues with multi-process support arriving in Firefox 48, pointing Firefox's desktop client toward a fully reworked foundation rather than incremental patches to the old one.
- If blocklists tighten with each release, add-on vetting becomes a standing quality gate rather than a reactive cleanup, changing what third-party extensions can realistically ship to Firefox users over time.
The trend: Mozilla is rebuilding Firefox from a 32-bit, single-process browser into a 64-bit, multi-process platform by promoting each architectural change through its developer channel before stabilizing it.