When using git bash on Windows, pressing ESC key for multiple times, then the input will be blocked. And after several seconds or more, it might show below information:
MyHome+tomxue@DESKTOP-I23OD70 MINGW64 /d $ Display all 5486 possibilities? (y or n)
I dig out several reasons and some solutions, but all not work. How to solve it?
The prompt you see is Bash's tab-completion prompt, informing you that it's about to offer too many completion suggestions.
One of Bash's default key-bindings is:
$ bind -p | grep complete
"\e\e\000": complete
i.e. ESC ESC NUL, which apparently also triggers on just ESC ESC, i.e. pressing the Esc key twice.
Esc sends the ESC byte, which is the same byte that starts the key-codes for various special keys; e.g. Shift-Tab would send the sequence ESC [ Z and so on. I don't know whether ESC ESC NUL is supposed to be the sequence for some special key, or if \e\e\000 is literally just Readline-speak for "Esc twice in a row" (as opposed to just \e\e).
Regardless, this key binding is triggered by pressing EscEsc and invokes tab-completion, as complete is the exact same action as if pressing the Tab key (which is listed by bind -p under "\C-i").
And if you invoke tab-completion at an empty input, Bash will just try to offer every possible command on the system – which will take a few seconds, during which Bash might appear to hang because it's scanning your whole $PATH for executables.