Looks like my rendering issue is not only due to the default rendition of window names with bells. It's part of it though. The rest is due to the change in screen v5 in how the formatting is handled. Especially, the removal of format modification, which I guess could be better documented. (More info in the upstream bug report.)
I guess the right way to fix this issue for me is to configure the rendition explicitely. For instance with the following config lines. rendition bell "bu 12;7" rendition monitor "b 12;7" rendition silence "u 4;7" Best regards, Celelibi
