bug#27816: 26.0.50; X protocol error: BadPixmap (invalid Pixmap parameter) on protocol request 55

[Eli Zaretskii]

> Date: Fri, 28 Jul 2017 08:28:10 +0000
> CC: 27816@debbugs.gnu.org
> From: Jean Louis <bugs@gnu.support>
> 
> Do you know any way to find out history of when user did git pull?

Yes, "git reflog".

Also, if you still have the previous build's binary, you could start
it and then type

  M-x emacs-version RET
  M-: emacs-repository-version RET

The latter will show the Git SHA1 signature of the last commit on
master at the time you synced with upstream master.