Modifying Config files

I just jumped into linux by installing ML4W on top of Fedora 44.

I thought it would be fun to start poking around by modifying a few config files to add some custom shortcuts, but I have no idea what concept I'm not grokking because this seems like a simple task and I can't get any results.

The keybindings are written in a file called

.config/hypr/conf/keybindings/default.lua

In this file, we have a long list of bindings that look like this:

hl.bind(mainMod .. " + CTRL + C", hl.dsp.exec_cmd("~/.config/ml4w/settings/calculator.sh"), { description = "Open the calculator" })

The shell file is a simple command to open the program like so:

flatpak run org.gnome.Calculator

To the best of my knowledge, I copied this format exactly, and created a new .sh file called mail.

hl.bind(mainMod .. " + N", hl.dsp.exec_cmd("~/.config/ml4w/settings/mail.sh"), { description = "Open Thunderbird" })

mail.sh is definitely placed in the right folder and is an exact copy of the terminal command that opens the program.

flatpak run org.mozilla.thunderbird

But for whatever reason, my new keyboard shortcut doesn't work at all. What am I not understanding about this process that would complicate such a simple looking task?