CardBook in v152 can't scroll window to save new entry or edited contact

The problem seems to be the lack of scroll bars. This is actually a Cardbook problem, not a Thunderbird one. I remember running into a similar bug several months ago and it was eventually fixed. You should contact the developer about that (difficult, I know - I'm a user, too.) https://gitlab.com/CardBook/CardBook/activity Perhaps they are already aware of it. In the meantime a workaround that works for me on Windows is to use the <Ctrl+Plus> and <Ctrl+Minus> key combination to shrink and expand the text in the edit window until you can get at the buttons. Or you can keep hitting the Tab key to cycle the focus through all the controls until you (blindly) land on the Save button. It will take some trial and error.