The development of next generation of pcmanfm was initiated last week.
Now the source code has landed in git.
It's still very basic and many features in the original pcmanfm are
However the major ones already work, especially tabbed browsing.
Please give it a test.
You have to install libfm before compiling pcmanfm.
Later the new pcmanfm and libfm will be developed in parellel.