Well, look at that! I went to make myself a drink, came back and decided to look over some other Plasma repos and immediately realized that I forgot Plasma is still in Beta and haven’t bumped version to 6 yet.
The solution from those repos is rather than following Kdevelop’s template, just change this:
find_package(KF6 REQUIRED COMPONENTS
Plasma
# Some other modules
)
To this:
find_package(KF6 REQUIRED COMPONENTS
# Some other modules
)
find_package(Plasma 5.90.0 REQUIRED) # Plasma 6 Beta 1.
Let hope that I don’t find more problems.