I can reproduce using pyright, starting with emacs -Q:
M-x eglot
(setq flymake-show-diagnostics-at-end-of-line t)
Using the following file:
```
def print_hello():
print("hello")
unknown_function
def another_function():
pass
```
You need to resize your window so that flymake diagnostics are displayed on multiple lines:
Place your cursor on the `unknown_function` line, and then press down. Your cursor will endup at the end of the current line instead of the next line.
Please tell me if you need more detail.
Thank you.