While version 5.15 remains the recommended Qt version for compiling QGIS, we've been hard at work adding full support for Qt 6 builds of QGIS. This is necessary in order to support modern desktop requirements, such as full compatibility with Wayland based Linux environments and for optimised Apple silicon builds.
QGIS 3.36 brings support for running Python under Qt 6 builds, and enables use of the PyQGIS library within Qt 6. This is a significant milestone in our ongoing journey towards full support for Qt 6!
This feature was funded by QGIS.org