AttributeError: 'NoneType' object has no attribute 'replace'

[koreno]

Description

Set GitGutter to compare to some branch, and got this:

Traceback (most recent call last):
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/tasks.py", line 65, in run
    task.run()
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/tasks.py", line 23, in run
    self.target(*self.args, **self.kwargs)
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/handler.py", line 806, in task_fn
    return resolve(chunk.decode('utf-8').strip())
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/promise.py", line 137, in resolve_fn
    self._do_resolve(new_value)
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/promise.py", line 149, in _do_resolve
    callback(new_value)
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/promise.py", line 113, in callback_wrapper
    resolve_fn(result)
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/promise.py", line 137, in resolve_fn
    self._do_resolve(new_value)
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/promise.py", line 149, in _do_resolve
    callback(new_value)
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/promise.py", line 107, in callback_wrapper
    result = callback(resolve_value)
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/commands.py", line 161, in <lambda>
    compare=self.git_handler.format_compare_against(),
  File "/home/ofer/.config/sublime-text-3/Installed Packages/GitGutter.sublime-package/modules/handler.py", line 259, in format_compare_against
    comparing = comparing.replace(repl, '')
AttributeError: 'NoneType' object has no attribute 'replace'

Support Info

• Sublime Text 3211
• Platform: linux
• Arch: x64
• GitGutter abfbb68
• Install via PC: True
• git version 2.31.0
• mdpopups 3.7.2
• markdown 3.2.2
• pygments 2.1a0
• jinja2 2.10.1