This morning I ran Synaptic, to update my system. The MLT framework was updated, so, I updated my system.
Not everything ran well. The video editor Open Shot complains it can't find the Frei0r plugins(without Frei0r plugins, its effects capabilities are decreased a lot). Since Frei0r uses MLT, something must have happened between these two (MLT and Frei0r).
If someone is experiencing the same problems, or already found a way to fix this issue, I would like to ask for help.
Thanks in advance,