ArcThumb

citrussoda-com·CitrusSoda.ArcThumb

Windows Explorer thumbnail and preview handler for archive files and ebooks.

ArcThumb is a Windows Shell Extension that adds thumbnail icons and preview-pane previews to Windows Explorer for archive files and ebooks. When a supported file contains images, ArcThumb decodes the first one and shows it as the file's thumbnail; the preview pane renders a larger version. Supported containers: ZIP, 7Z, RAR, TAR and their media variants (CBZ, CB7, CBR, CBT), plus ebooks in EPUB, FB2, MOBI, AZW, and AZW3. Images inside are decoded from JPEG, PNG, GIF, BMP, TIFF, ICO, and WebP. Optional JPEG XL support is available in custom builds. ArcThumb is a Rust-based successor to CBX Shell and DarkThumbs. A bundled configuration GUI lets you toggle formats, set decode limits, and register or unregister the extension. Installs per-user by default with no administrator privileges; running the installer elevated registers the extension machine-wide instead, which is required when Explorer runs at high integrity (such as Windows Sandbox). Requires Windows 10 or later on x64.