Thank you for your response.
I found out that the problem was mode - as I ran the slint command from the sce file, changing to mode(0) solved the report.
On the other hand, it is inconsistent that message "Module developed with the contribution of CNES."was shown, but the report itself is not. This confused me, as I expected it should also show the report.
Should I report bug on gitlab - show everything or nothing in console?
This advertising message is completely odd (moreover slint is not a “module”). If all contributors had done like this, using Scilab would be really annoying. As far as I am concerned, I have never had such an idea in my contributions (the copyright in the source file is enough). Reporting an issue would be a good idea, with a possible resolution under the form of the removal of the message + the addition of a CNES copyright notice in the source of slint gateway (scilab/modules/slint/sci_gateway/cpp/sci_slint.cpp · minor · scilab / scilab · GitLab).