dmenu 4.9_1 is not working for me. I believe this is an upstream issue, first reported at https://lists.suckless.org/dev/1902/33245.html in February of 2019.
When I open dmenu_run, and input anything, nothing shows up in dmenu and the program doesn't open.
The issue also occurred on Linux, but Fedora, at least, seems to have fixed it with their dmenu-4.9-3. On Linux, I have also found that the git version works.
I have also found that if I'm running an input manager, fcitx-mozc in my case, the latest dmenu will work. The mailing list thread linked above shows the commit that seems to have broken it--later there was a fix that should be in our version, but that doesn't work for me.
For me, the only workarounds have been to either be running an input manager or downgrading to 4.8.
Mateusz fixed this already. Dmenu-4.9_6 no longer has the problem. Thank you Mateusz! I don't seem to be able to close this, only to add comments, but this can be closed as FIXED. Thanks again. :) If this comment does close it, again, thank you.