
ImageGlass is the image viewer I use and recommend and its maker recently issues a major update to the app that improves performance and adds support for the Mac and Linux.
“ImageGlass 10 marks a massive milestone,” the announcement post explains. “[It’s] a complete rewrite from the ground up. Previous versions relied directly on Windows APIs, keeping ImageGlass locked to a single OS. ImageGlass 10 is rebuilt on .NET and Avalonia, bringing a single, unified codebase natively to Windows, macOS, and Linux.”
I use ImageGlass semi-exclusively for its minimalist image viewing capabilities, but I also use it to convert between file formats when Affinity can’t open a file for editing. But ImageGlass offers a full set of functionality that goes well beyond that, including tools like color picker, image crop, image resize, lossless compression support, and more.
With this new release, ImageGlass also gains native HDR support, an integrated SVG rendering engine, extensible plugin support, and dramatically faster startup times. As before, ImageGlass is still free, though the free version is called ImageGlass Classic, while a new ImageGlass Pro edition is $14.90 for a one-time license for individuals (and $69 for Pro Team) and adds additional capabilities like a live HDR Tone Mapper tool, free and margin panning, File Watcher, custom mouse click remapping, settings lock for managed rollouts, and feature locks for shared devices.
I use ImageGlass every day and highly recommend it. You can find out more on the ImageGlass website.