Changelog

+ New

• JPEG XL export. Two new output formats, JPEG XL and JPEG XL Lossless, work from every image RasterFox opens: JPEG, PNG, WebP, AVIF, HEIC and JPEG XL itself. JPEG XL is the newer format that keeps transparency and full color depth and gets smaller files than JPEG at the same quality. Lossless keeps every pixel exactly, transparency included. A JPEG saved as JPEG XL Lossless is repacked rather than re-encoded, so it comes out smaller with nothing lost, and the original JPEG can be rebuilt from it byte for byte
• JPEG XL files open in RasterFox. Optimizing one with "Same as Original" keeps it lossless or lossy, whichever it was, and never makes it bigger. Choosing JPEG XL for a lossless file makes it lossy. JPEG XL files can also be resized, upscaled, have their background removed, or be converted to any other format
• JPEG XL quality and effort controls in Settings and in the compare window's inspector, set from each preset: High Quality 95, Balanced 85, Small Size 70. Higher effort makes smaller files and takes longer to encode

~ Improved

• The output format choice in Settings is now a menu, so the longer list fits
• File ▸ Open and the menu bar item now accept AVIF files. Before, AVIF could only be dragged in or added from the main window

× Fixed

• macOS 27 Golden Gate compatibility. The preset and format pickers in the toolbar came up blank on macOS 27: the menus still opened and the right item was checked, but the control itself showed no title. The toolbar in Golden Gate now draws its menus icon-only unless told otherwise, so the pickers now ask for their titles explicitly and read as they did on macOS 26

× Fixed

• Converting a grayscale image to WebP works. Grayscale JPEGs and PNGs — 8-bit or 16-bit, with or without a gray color profile — failed every time WebP was the output format, and had since the first release that offered the conversion. The WebP encoder only takes 8-bit color pixels, and grayscale images were being handed to it as-is and refused. Grayscale, grayscale with transparency, and 16-bit images of any kind are now converted to the layout the encoder expects first. Transparency is kept where the original had it; opaque images stay opaque

× Fixed

• High Quality no longer bands smooth gradients. Logos and artwork with big, slow color ramps — the Firefox logo is the classic case — were being squeezed onto a 256-color palette that can't carry a 17,000-color gradient, and the quick analysis that decides the compression route genuinely can't tell those images from ones a palette handles perfectly. So at quality 90 and up RasterFox now measures the finished result instead of trusting the guess: if the palette version falls short, the image is redone keeping full color, with similar colors merged only within a strict per-channel budget so gradients hold their ramps. Where a faint step survives it's now a clean, evenly spaced one — an earlier cut of this produced ragged contour rings, and the merge was reworked onto an even grid so that can't happen. Gradient-heavy images can come out larger than they did in 3.1.2; that size was being bought with visible banding
• Clicking a row in the results list selects it again. A double-click gesture on each row was swallowing the single clicks the list needs for selection — arrow keys worked, the mouse didn't. Double-click still opens the compare window, and the right-click menu now works on a multi-row selection too, with a single Remove for all of them
• The progress bar in the toolbar no longer sits in its own outlined capsule during a batch

~ Improved

• PNG compression is more accurate at every preset and about 30% faster, after a deep pass over both quantizers. Flat colors no longer drift slightly during palette refinement, a hashing quirk that corrupted the top-left pixel of every dithered image is fixed, transparent edges get cleaner treatment, and simple graphics now regularly come through pixel-perfect. Balanced output sizes are essentially unchanged with the quality gains
• High Quality is smarter about images that used to be stored oversized: renders with smooth shading that previously shipped as bloated files now compress to a fraction of the size at equal or better quality, because the palette and full-color routes are both tried and the smaller result wins whenever quality allows

× Fixed

• Optimizing an already-compressed image could hand back a bigger file than you started with, and save it. A photo that had already been squeezed hard was re-encoded at the preset's quality, and whatever came out was what you got — in one case an 88 KB photo came back at 140 KB, 60% worse. When optimizing can't improve on what you already have, RasterFox now keeps your original untouched. Converting to another format, resizing, and removing a background are unaffected: those change what the file is, so a larger result is a fair trade for the thing you asked for

× Fixed

• Background removal could take the artwork along with the background. On a logo sitting on a solid colour, the parts of the design closest to that colour — a dark green or dark blue against near-black, say — were close enough to be treated as background and removed, leaving holes where the design used to be. Removal now works out how much room there is between the background and the nearest colour in the artwork, and stays inside it
• Colour-based removal started at a setting that was too strong for most images. Tolerance now starts at 15 rather than 30. Measured across a range of real photographs and graphics, 30 was higher than the setting any of them actually needed, and on a design with colours close to the background it was enough to erase them. If you have already moved the Tolerance slider yourself, your setting is kept
• Auto mode picked its removal strength from how varied the edge of the image was, which two images could sit either side of by a rounding difference — and one of those two answers took the artwork out. It now measures the distance between the background and the nearest colour in the picture, which is what actually decides how far removal can safely go

+ New

• Background removal clears the gaps inside a design, not just around it. The inside of an "O", the hole in an "e", the space enclosed by a ring — removal used to start at the edges of the image and work inwards, so anywhere the artwork closed off completely was never reached no matter how far you pushed Tolerance. Turning Tolerance up only ever made it start eating the artwork instead. It's on by default; switch "Remove enclosed areas" off for photographs, where it can take out detail that happens to match the background, like a dark shirt against a dark wall
• PNG is now one of the Convert To options, alongside WebP and AVIF

× Fixed

• Images converted to PNG were still called .jpg. Removing a background always produces a PNG, because that's what carries transparency — but the result kept the original name in the preview, in the file list, and in the file actually written to disk. Opening it later showed a PNG wearing the wrong extension
• Local AI shifted the colours of your image as you moved Mask threshold. Yellows washed out towards white and reds lost their depth, so tuning the cutoff quietly recoloured the picture. The threshold now changes only what's kept and what's removed, and the colours hold steady across the whole range
• Local AI sometimes gave up on an image for no reason and quietly fell back to colour matching. It was misreading how much of the picture it had found — on one test image it measured 12% when the real answer was 44% — and abandoning anything it thought was too small
• Turning Tolerance up could let the background leak into the artwork. The check that stops the removal crossing a hard edge was itself loosened as Tolerance rose, so the setting you'd reach for to catch a stubborn patch was undoing the thing holding the removal back
• The progress bar in the compare window pushed the image down and let it snap back. It now sits over the top edge of the image, so nothing moves while a change is applied

~ Improved

• Auto looks at the image before choosing how to remove the background. Flat artwork on a solid colour — logos, badges, lettering — was going to subject detection, which lifts the whole design as one silhouette and leaves every scrap of background trapped inside it exactly where it was. Auto now measures the border first: a solid one means colour matching, a busy one means Local AI. Photographs behave as they did
• With background removal on, formats that can't hold transparency are no longer offered. "Same as Original" used to stay selectable for a JPEG and then quietly produce a PNG anyway; for anything that isn't already a PNG you now choose between PNG, WebP and AVIF

× Fixed

• Moving RasterFox to Applications failed when an App Store copy was already there. It reported that macOS wouldn't allow the replacement and never offered a way through. macOS installs App Store apps in a way that only Finder can change, so RasterFox now asks Finder to do it and you get the usual password prompt — the same one you'd see dragging that copy to the Trash yourself. Your App Store purchase is read and applied before anything is moved, and the old copy goes to the Trash rather than being deleted
• Running from the disk image wasn't always recognised. RasterFox only noticed when the download flag was still set, so in some cases it sat quietly on the disk image reporting itself as properly installed. Nothing you set up there survives ejecting it, so it now says so whenever it's running from an image

+ New

• Copy Diagnostics, in Settings ▸ About. One click puts a short report on the clipboard — where RasterFox is installed, whether that location lets macOS remember permissions, how saving is set up, and any recent save problems — ready to paste into a support email. No personal information goes in it, and paths are shortened so your account name doesn't travel with it

× Fixed

• Being asked to allow the same folder for every single image. When macOS refused a save — which on a direct download usually means it hasn't been granted access to your Desktop, Documents, Downloads, iCloud Drive or an external disk yet — RasterFox put up its own panel per file, so a drop of 200 photos meant 200 panels. It now asks once for the folder and applies your answer to everything else headed there
• "Ask each time" asks again. On direct downloads the setting quietly saved alongside the originals instead of asking where to put each file
• Save Location could disagree with itself before you ever picked one. The footer, Settings, and the optimizer each assumed a different default on a fresh install; all four now start on the same custom folder

~ Improved

• RasterFox offers to move itself to your Applications folder, in one click. Opened from a disk image or straight out of Downloads, macOS gives an app a new temporary home every time it launches, so no folder permission you grant is ever remembered — which is why you can end up allowing the same folder over and over. RasterFox now spots this on launch and offers to move itself and reopen from Applications, where permissions stick. You can also just carry on where you are
• macOS's own permission prompts explain themselves. They used to show Apple's generic wording; they now say what RasterFox wants the folder for

~ Improved

• The paid features have a name. Settings ▸ License read a bare "Licensed", which never said what the tier was called, so the pricing on the website and the status in the app were using different words for the same thing. It now reads "RasterFox Pro", the trial counts down a "Pro trial", and the buy button and status line name the tier instead of listing the features twice

× Fixed

• Confetti celebrates license activation again. It had been hiding behind a Settings toggle that defaults off; now it always fires, and the toggle governs just the fanfare sound

+ New

• A full interface redesign. RasterFox now uses native macOS windows, toolbars and controls throughout, with one vivid fox-orange accent, and it respects your light or dark appearance instead of forcing its own chrome
• Side by Side compare mode in the preview window: original and optimized in two panes with locked pan and zoom, plus a minimap in each pane showing where you are in the image. Click or drag the minimap to jump anywhere
• The optimizer panel in the preview window is now a proper inspector pane: attached to the window edge, resizable, remembered between launches, toggled with Opt-Cmd-I
• Settings is a real macOS settings window with native tabs, and every pane uses standard grouped forms
• Keyboard throughout: Cmd-O adds images, Space previews with Quick Look, Return opens the compare window, Cmd-Delete removes, Cmd-R reprocesses, Cmd-S saves. Arrow keys navigate the list and every control shows a focus ring again
• Right-click any result row for the full set of actions; the row buttons appear on hover instead of crowding every row
• What's New in the app menu: the full changelog in a native window, shown once automatically after each update

~ Improved

• Big batches feel much faster: the results list no longer repaints itself dozens of times a second while images process
• Result rows read calmly: sizes in aligned figures, one highlighted savings percentage, and honest progress bars instead of animated placeholders
• Direct-download builds never show sandbox permission prompts. Files save alongside originals with no folder access dance, and the permission flow only exists for sandboxed App Store builds
• Fit view in the preview window renders smoothly; pixel-exact rendering now kicks in only when you zoom past fit
• Celebrations respect Reduce Motion and share one Celebrations toggle covering confetti and sound
• VoiceOver can reach every control, and every icon button has a label and tooltip

× Fixed

• Pressing Cancel in the folder access dialog actually cancels processing instead of carrying on
• The Save button in the preview window shows up reliably; its toolbar previously failed to render at all
• Escape properly cancels the onboarding and migration sheets
• Pasting images no longer triggers two competing paste handlers

~ Improved

• Migrating a Mac App Store purchase now tells you it happened. The unlock used to be completely silent, and the one thing it needs from you, an email address for a permanent license key, was easy to miss in settings
• The disk image explains itself now, including a note for App Store buyers to open RasterFox from the disk image before installing it

× Fixed

• Restoring an App Store purchase when the App Store copy is already gone now spells out the order to follow, including moving RasterFox aside before reinstalling from the App Store so the two don't overwrite each other

~ Improved

• Checks for updates shortly after launch. Previously the first automatic check could be a day away, so a new install would sit on an old version

+ New

• First direct release, distributed outside the Mac App Store with automatic Sparkle updates and a Homebrew cask
• Automatic migration for Mac App Store customers: RasterFox detects your previous purchase, unlocks instantly and offline, and can email you a permanent license key for your other Macs
• 14-day full-feature trial. After it ends, RasterFox stays free forever and keeps compressing unlimited images with the Balanced preset. A one-time license unlocks every preset, unlimited batches, WebP output, the compression settings, 3x and 4x AI upscaling with every model, unlimited background removal, adjustable concurrency, custom save locations and filename templates, and the alternative app icons
• A License tab in Settings for activating, deactivating and recovering your key, plus one-click activation from the purchase email
• An About tab in Settings, replacing the old system about panel, with the version, your licensing state, and a manual update check
• The Our Apps tab now reads the live app list from skulkworks.dev, so new SkulkWorks apps appear without an update

~ Improved

• No longer sandboxed, so compressed images can be written alongside the original without granting folder access first
• Cross-promotion links now point at each app's page on skulkworks.dev rather than the App Store, which had gone stale for apps that ship direct

× Fixed

• Three build files (the StoreKit configuration, the test plan and an xcconfig) were being copied into the app bundle on every release