The LGPL requires that you're able to debug, modify, and replace the library in question, in this case, Qt. > You may convey a Combined Work under terms of you

The LGPL requires that you're able to debug, modify, and replace the library in question, in this case, Qt. > You may convey a Combined Work under terms of your choice that, taken together, effectively do not restrict modification of the portions of the Library contained in the Combined Work and reverse engineering for debugging such modifications. However, DuckStation supplies prebuilt bundles that don't allow for that, in the case of Windows.