When you run this executable, you will be prompted to log into a Qt account. You do not need to log in for open-source versions 5.15.2 and earlier.
Let’s break down the filename. Understanding the nomenclature is the first step to mastering Qt deployment. qt-opensource-windows-x86-5.15.2.exe
Since you are using the open-source version (LGPL/GPL), you must comply with license terms. The official "Qt Licensing" paper describes: When you run this executable, you will be
Useful link:
Qt 5.15.2 Licensing Overview (PDF) (printable as PDF) Useful link:
Qt 5
By 5.15.2, the Qt5 codebase had been polished for over five years. Nearly all critical bugs were fixed. Qt 6 introduced major architectural changes (e.g., removing Qt Widgets' reliance on OpenGL, changing the graphics stack). For business-critical applications where "it just works" is the requirement, 5.15.2 is the safe choice.