I created a docker container with an up-to-date Fiji and wrote python script than runs fine in headless mode locally on my machine.
When I now run the docker image Fiji starts in headless mode and the “Welcome ImageJ2 & Co” text shows up as html-like text inside the console. And this prevents my script from being executed.
The current workaround is to start Fiji inside the docker in headless mode once without calling the script and wait a while. And then start the Fiji in headless mode again now calling the script. The 2nd time the “Welcome” stuff will not show up any more and the script runs as expected.
This is a bit strange, but I have no idea, how to prevent that. Is there a way to supress that “Welcome” stuff from blocking my script?