Hi Bugsounet
You are very much right!!! Somehow, i386 has been added to my package manager, and did damage when installing MMM-GoogleAssistant and EXT-Detector.
bo@mm:~$ dpkg --print-foreign-architectures which gives:
i386
I remove it with: “sudo dpkg --remove-architecture i386” and now the installation runs like a charm
Thank you very much for your help!