I've noticed that my Kdenlive 18.12.3 on Arch is missing a bunch of color correction effects, such as curves, white balance, and so on.

I checked on a windows system I have access to with kdenlive 18.12.1 and the effects are all there.

Any idea what I'm missing/different on Arch (or my laptop hardware?) that might cause these effects not to show up?

Here is what my effects list looks like:

It could be that your installation is not complete. Please try with the AppImage from the download page.

I finally tried moving my kdenliverc file. Then when I started kdenlive it warned me that the frei0r-plugins package was missing. After I installed that, all the colour correction filters were back.

For some reason frei0r-plugins is not registered as a dependency, or even an optional dependency suggestion, in the Arch Linux package. I will report this to the package maintainer.