bug#69246: 30.0.50; persistent key input delay after using vc commands in pgtk

[Nick OBrien]

A few updates:

- After using my normal emacs config with GTK_IM_MODULE=none for a few
  days, I did not encounter the input lag. When previously using
  GTK_IM_MODULE=fcitx, I would have encountered the lag multiple times
  during the same pattern of use.

- I tried installing ibus and following the steps in the original bug
  report with GTK_IM_MODULE=ibus. I encountered the same lag I did with
  fcitx.