[bug] crash when editing message

[Young-Lord]

Server: Zulip cloud server
Client: main branch
Python: 3.11
self.model.initial_data: {'zulip_version': '9.0-dev-642-g9d469357ea', 'zulip_feature_level': 237, 'zulip_merge_base': '9.0-dev-605-g47a5459637', 'realm_message_content_edit_limit_seconds': None}
log:

Traceback (most recent call last):
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/zulipterminal/cli/run.py", line 578, in main
    ).main()
      ^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/zulipterminal/core.py", line 691, in main
    self.loop.run()
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/main_loop.py", line 287, in run
    self._run()
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/main_loop.py", line 385, in _run
    self.event_loop.run()
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/main_loop.py", line 790, in run
    self._loop()
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/main_loop.py", line 827, in _loop
    self._watch_files[fd]()
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/raw_display.py", line 416, in <lambda>
    wrapper = lambda: self.parse_input(
                      ^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/raw_display.py", line 515, in parse_input
    callback(processed, processed_codes)
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/main_loop.py", line 412, in _update
    self.process_input(keys)
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/main_loop.py", line 513, in process_input
    k = self._topmost_widget.keypress(self.screen_size, k)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/zulipterminal/ui.py", line 324, in keypress
    return super().keypress(size, key)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/container.py", line 1135, in keypress
    return self.body.keypress( (maxcol, remaining), key )
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/container.py", line 2316, in keypress
    key = w.keypress((mc,) + size[1:], key)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/container.py", line 1626, in keypress
    key = self.focus.keypress(tsize, key)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/container.py", line 2316, in keypress
    key = w.keypress((mc,) + size[1:], key)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/zulipterminal/ui_tools/views.py", line 651, in keypress
    return super().keypress(size, key)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/container.py", line 1135, in keypress
    return self.body.keypress( (maxcol, remaining), key )
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/zulipterminal/ui_tools/views.py", line 249, in keypress
    key = super().keypress(size, key)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/urwid/listbox.py", line 968, in keypress
    key = focus_widget.keypress((maxcol,),key)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/data/com.termux/files/home/.local/share/pipx/venvs/zulip-term/lib/python3.11/site-packages/zulipterminal/ui_tools/messages.py", line 1048, in keypress
    if self.model.initial_data["realm_message_content_edit_limit_seconds"] > 0:
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: '>' not supported between instances of 'NoneType' and 'int'