If you are trying to maintain an older workflow or need to know how it stacks up against modern versions, The Legacy of Lightroom 5.6
Lightroom 5.6 was one of the final iterations of the "perpetual license" era before Adobe transitioned fully into the Creative Cloud (CC) subscription model. For many photographers, this version represents a "goldilocks" zone of performance and essential features without a monthly fee.
The ability to fix irregular shapes (like a stray power line) rather than just circular spots.
A one-click fix for skewed horizons or distorted architectural lines.
While it runs well on Windows 10, it may encounter "legacy" errors on Windows 11 or modern macOS versions (like Sonoma), which have dropped support for older 32-bit installers often bundled with 64-bit apps.