I am using the latest emacs 26.1 compiled with msys2/mingw64.

There is problem for a few weeks.

I am not able to give a recipe to reproduce it but the symptoms

are :

- slow ido behavior, much slower than it used to be

- sometimes erratic behavior with the keyboard events

Example: M-x find-library <some string>, get a bunch of choices,

try to navigate them and the cursor jumps erratically between choices...

before trying to enter the debugger, then emacs is stuck and I have

to kill it.

The performance issue has also been reported here:
https://github.com/DarwinAwardWinner/ido-completing-read-plus/issues/143

(probably wrong place to report it btw).

Don't know if/when I will find time to investigate. 

But if anybody has suggestions where to look I'll do my best.

Regards,

Fabrice