skhd: Doesn't seem to work on Big Sur 11.3.1

Sure. I haven’t used skhd in a while though from what I remember it seemed to work the last time I tried.

For those experiencing this issue, I found that Chrome (or in this case Chrome via Vivaldi Browser) on my mac triggered this when I was simply on a login page for a website (in some cases)

Yet, when I tried things to troubleshoot like: https://github.com/koekeishiya/skhd/issues/172#issuecomment-1028389241, the loginwindow process was flagged as the culprit. But, killing this process or locking/unlocking my mac did not resolve this.

Every time I attempted to run skhd -V in my terminal to troubleshoot the program starting, I would get errors like mentioned here: https://github.com/koekeishiya/skhd/issues/172#issuecomment-916281758 i.e. skhd: secure keyboard entry is enabled by (2638) 'terminal'! abort.. regardless of the terminal program I used (I have both hyper and alacritty).

Turned out the problem was just because I was on a login page for a web app in Chrome. Closing the tab with the login screen resolved the issue immediately and skhd started working right away.

Just something to consider…may be the cause of your problem as well.

For me it took a couple of trials to understand what was happening.

First, I tried to run skhd using /usr/local/opt/skhd/bin/skhd rather than the brew services start or restart.

The command above gave the following error: skhd: secure keyboard entry is enabled by (2638) 'terminal'! abort..

Now, despite having secure keyboard turned off on my terminal, it seemed that some app(s) is controlling that! so I ran ioreg -l -w 0 | grep SecureInput.

That will tell you the process ID (kCGSSessionSecureInputPID) of the application that has Secure Input enabled. You can then use ps auxww | grep NNN to find the process with the specified pid.

For me, the culprit turned out to be Keybase, uninstalling that gave me my skhd back!

Source: Disable Secure Input