* `Disallow_error_recovery_on_key_release` -- currently needed to handle one
  specific hard-to-recover-from error in `snapshot_canvas`. Subject to
  removal, but I'll document it here as long as I support it. Please
  [let me know](http://akkartik.name/contact) if you find a new need to read
  or write it.
## Variables you can set/read

  hard-to-recover-from errors. Right now I'm only aware of one such (see
  driver.love): calls to `love.graphics.newCanvas` can fail at the SDL2 layer
  if a computer doesn't have enough video RAM to perform them. In response,
  set this variable before and unset after to prevent the system from
  repeatedly retrying something that is unlikely to recover. In particular,
  prevent settings from being saved to disk during an error state, thereby
  perpetuating the error.

  hard-to-recover-from errors. Right now I'm only aware of one such: calls to
  `love.graphics.newCanvas` like the one in `snapshot_canvas` can fail at the
  SDL2 layer if a computer doesn't have enough video RAM to perform them. In
  response, set this variable before and unset after to prevent the system
  from repeatedly retrying something that is unlikely to recover. In
  particular, prevent settings from being saved to disk during an error state,
  thereby perpetuating the error.

        if not Disallow_error_recovery_on_key_release then
          error_frame_keys_down[a] = nil
          App.run_frame = main_run_frame
        end