I'm using kdenlive 15.12.3 shipped with openSUSE Leap 42.1

In the blacklisted_effects.txt file, there is a number of frei0r effects listed under "# effects with XML UI" comment. The XML files corresponding to each of these effects are present in the effects directory.

These blacklisted effects do not appear on the Effects List in kdenlive GUI. However I'd like to ask if it is possible to use these effects somehow, maybe by editing some files in the project or something like that?

As I understand it - effects get put on the black list because they crash Kdenlive when people attempt to use them in the kdenlive application.

I thought it was not the only reason to blacklist an effect. According to this README (line 135):

All effects with a custom XML GUI need to be blacklisted.

On startup, Kdenlive scans the effects directory and automatically creates GUI for effects found there. I assumed, that effects that require custom GUI need to be excluded from this scan, and it's achieved by putting them on the blacklist. However, I thought they might be available, just not loaded automatically.