This release includes breaking changes for platform teams planning a safe upgrade.
✓ No known CVEs patched in this version
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Summary
AI summaryFixed Relay fallback instability during large transfers and handled edge‑case file named "nul" on Windows.
Full changelog
🚀 What's New in v3.9.3
(Note: v3.9.2 was a silent hotfix dedicated to resolving shortcut and locale issues specifically for the Microsoft Store release. All those fixes are included here.)
This release focuses on battle-tested reliability for massive transfers, smoother folder handling, and better edge-case compatibility.
⚡ Battle-Tested Reliability
- Unbreakable Relay Fallback (The 7GB Fix): We identified and fixed a critical edge case during a 7GB real-world transfer from Russia. When a direct WebRTC connection drops and
fflautomatically falls back to Relay mode to resume, the browser'sTransformStreamcould become unstable and drop the connection after 300 seconds. We've patched this browser-level instability and tightened overall connection resilience. - Sidecar Upload Accuracy: Fixed an issue where Sidecar uploads could fail due to the system overestimating or underestimating the final upload payload size.
☁️ Smarter Server Uploads & Folder Handling
- Upfront Points Confirmation: When using the Server Upload mode (
--upload),fflnow calculates the total cost and asks for confirmation before starting the upload.- Previously, exact folder sizes were unknown until processing, preventing accurate upfront point calculations. This is now fixed.
- Auto-Accept: You can now pass the
--yes(or-y) flag to automatically accept the point deduction and bypass the prompt, which is perfect for headless scripts.
- Real-time Folder Scanning: When sharing massive folders,
fflnow displays a live progress indicator while calculating the total size, so you always know the CLI is actively working and hasn't frozen.
🐛 AI Workflows & Edge Cases Fixes
- Claude Code Windows Fix (The
nulbug): Fixed a crash that occurred when trying to share a folder containing a file literally namednul. This specific ghost file is often generated by AI agents like Claude Code on Windows, andfflcan now handle (and gracefully ignore) it without breaking the folder share.
📦 Which file should I download?
- If you want a single file that runs everywhere, across OSes? choose APE (
ffl.com/fflo.com). - If you want platform-optimized size/perf, choose a native build. 🙂
- On Linux and unsure about glibc (or on musl)? -> APE
ffl.comis the safest choice.
ℹ️ On the first run of a native build, the app performs an internal extraction step (by pyapp), so startup is temporarily slower once.
The install scripts pre-warm this step; manual downloads will see the one-time delay.
APE builds (ffl.com/fflo.com) are single-file and do not have this first-run warmup.
Windows (native)
- x86_64 →
ffl-v3.9.3-x86_64-windows.zip
Unzip to getffl.exe.
Linux (native)
We publish two glibc baselines. Pick the highest baseline that does not exceed your system glibc:
-
glibc 2.39+ — smaller & faster
ffl-v3.9.3-manylinux_glibc2.39-x86_64-linux.tar.gz- Best for newer distros (e.g., Ubuntu 24).
-
glibc 2.28+ — widest compatibility
ffl-v3.9.3-manylinux_glibc2.28-x86_64-linux.tar.gz- Works on older distros (e.g., Ubuntu 20); larger due to additional internal linking.
⚠️ If your system is musl-based (e.g., Alpine) or you’re unsure about glibc, prefer APE
ffl.com.
macOS (native)
- Apple Silicon (arm64) →
ffl-v3.9.3-aarch-darwin.tar.gz - Intel (x86_64) →
ffl-v3.9.3-x86_64-darwin.tar.gz
The archive unpacks to a single ffl binary.
🧰 APE (cross-platform single file, zero external deps)
ffl.com— Single-file build that runs natively on Linux, macOS, Windows, FreeBSD, OpenBSD 7.3, NetBSD, BIOS, and Android (Termux).fflo.com— Alternative APE build that is exactly aligned with the open-source repo (no additional/proprietary addons).
As a result, features that require closed-source components—such as upload to server (e.g.,--upload)—are not available.
For a deeper comparison between native and APE, see the README’s notes.
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