Comment 6 for bug 1878718

a) When I do a short press, then immediately after a release, the next option is selected (the dialog does not have time to appear even).
b) When I do a long press, then the options start to circle very quickly until I release the key (see the screencast)

I think the bug is caused by this: When you do Super+K, you hold Super and press K repeatedly to switch the options. After you release the Super key, the option is confirmed. When you use the fn key, there is just one key, so after releasing, it immediately selects the option.