According to the text just above https://docs.python.org/3/library/exceptions.html#EnvironmentError, `EnvironmentError` has been an alias of `OSError` since Python 3.3. Replacing it makes the code more consistent since `OSError` is used in other places in the code too.
The timeout is 0.25 seconds. Printing 0.25 instead of 0.250000 looks a lot nicer and a resolution of 10 milliseconds should be enough for this warning message anyways.
The hints, once set with `glfwWindowHint()`, retain their values until changed again. This means, that the `GLFW_DECORATED` hint only needs to be set once, even on non-macOS.
Most macOS Apps have a Help menu as the last menu item in the menu bar. They usually have a menu item with the keyboard shortcut <kbd>⌘</kbd>+<kbd>?</kbd>, which shows some kind of help or documentation. I named the menu item "Visit kitty website" and let it open the kitty website as documentation.
macOS also magically adds a search feature to the help menu.
`addItemWithTitle:` can be used instead of `initWithTitle:`. It returns an `NSMenuItem`, which removes the need for allocating an `NSMenuItem` manually and releasing it again.
`glfwGetCocoaKeyEquivalent()` in `glfw/cocoa_window.m` expects the returned characters to be of type `unichar`, which won't work for all unicode characters because it is defined as `unsigned short` according to https://developer.apple.com/documentation/foundation/unichar?language=objc, which is only guaranteed to be at least 16 bits in size. The code calling this function also expects the encoding to be UTF-16.
When I added the various keys in https://github.com/kovidgoyal/kitty/pull/1928, I missed these facts. This means, that `glfwGetCocoaKeyEquivalent()` will behave unexpectedly when called with any of the new-ish keys. Luckily this function is currently only used for determining the macOS shortcut for `new_os_window` but I plan on using it more in the future.
Some of the constants, e.g. `NSBackspaceCharacter` are UTF-16 constants, so we can't just use UTF-8 everywhere.
I fixed the problem by using either UTF-8 characters packed into a `uint32_t` or UTF-16 characters in a `unichar` and then converting them to a UTF-8 encoded char string.
`NSEventModifierFlagNumericPad` isn't guaranteed to fit in a `unichar`, which made this undefined behaviour. It also didn't work. I tried to make it work using `NSEventModifierFlagNumericPad` as a modifier instead, as can be seen in this commit, but couldn't get it to work either because the constants used are native key codes and not unicode characters. Therefore the numpad keys will be removed in the next commit.
