5.4.20 doesn't build for Qt 5.15~6.1

[Felix Yan]

But the enum is actually added since 6.2, according to official Qt documentation:

So it doesn't build on, for example, Qt 5.15:

[Gary Wang]

这个问题应该已经不再存在了，先 close 了（ps. 如果还存在的话在 developer-center 开个 issue）