Parallel instances of grc on Linux

Hi all,

I installed 3.8.2 and 3.9.0RC0 on my system (Debian 11 testing).

Both instances are running well but I want to distinguish/separate the
files which are opened when I start GRC. At the moment 3.8.2 is opening
file a + b and when I start 3.9.0, the same files are opened. Instead of
this I want 3.9.0 to open its files c + d (for example).

Is there a command line option available to determine a "working space"
or directory?

Thanks for reading.

Tom, DJ6TB