GUI does not work when Meld is called from command line

[seralouk]

I am using Meld on my macbook 2019, Catalina. I installed the latest Meld version compatible with catalina.

When I call meld from the command line, the GUI does not appear at all but the application is executed (i can see that it's open).

$ meld
Couldn't set the locale: unsupported locale setting; falling back to 'C' locale

(meld:764): Gtk-WARNING **: 09:34:23.340: Locale not supported by C library.
	Using the fallback 'C' locale.

I tried a bash script that I found in another open issue and it fixed the problem but only temporarily.

[rogeriofonseca]

I have the same problem with Catalina Version 10.15.7 when I run through the terminal.