I found that I again had the bug "getdeb.list.bck in sources.list.d". I don't know how to change or remove the files in the sources list. It's not a crucial issue, but it is quite irritating each time you do an update of sources to get in the terminal:Ignoring file 'getdeb.list.bck' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension. I would greatly appreciate any help and suggestions. Thanks.