Hello,
Because GSoC is ahead, I wanted to solve this issue. I've got a little experience in working with linux terminal, and I can say it works strange sometimes. Back to the issue - I do not think this problem is entire in code, more like it depends on terminal. I ran
tput rmam
which temporarily disables line wrapping, then run joplin and it seems fine for me. Everything looks to be fixed, the text aligned to the right does not overflow the text on the left anymore. So I wanted now to ask - if I am not mistaken - could we close this issue (since it's terminal-dependent error), or should I dig deeper?