On macOS, Qt 4.8.7 predates the strict notarization requirements of modern macOS versions. You may need to bypass "Gatekeeper" in System Settings to run the installer. Transitioning to Modern Qt
Downloading Qt 4.8.7 is a common requirement for developers maintaining legacy C++ applications or working with older versions of frameworks like OSG or early PyQt. While the industry has moved toward Qt 6, the 4.8.7 release remains the final and most stable version of the Qt 4 series. download qt 4.8.7
If using MinGW, ensure the version matches the installer (typically 4.8.2) to avoid binary compatibility issues. Linux Installation (From Source) On macOS, Qt 4