I notice a change when transitioning from GLFW 3.0 to 3.3. GLFW 3.3 doesn't register all keys when they are pressed almost instantly. Before (vs 3.0) all keys were registered by glfwGetKey(), with no problems. Now (vs 3.3) when I use glfwGetKey(), only the first key pressed is registered and only after the delay of the repeat keys is passed, that is, when the key starts repeating, GLFW register the key. When you add more than 2 keys at the same time, the problem becomes really apparent.

I was wondering, was something I am missing from the versions changes? Or is this bug?

I am using Linux (popOS).

Here is the code I am working on . in case you want to test it yourself.