Fix broken n_lines_unread calculation.

diff --git a/src/ircplom/tui_base.py b/src/ircplom/tui_base.py
index abfe67e111e7fa8d044b1eb94c5735cf197d1f57..4593bdce0e3caa7fd0dccede054b565b4a35ba01 100644 (file)
--- a/src/ircplom/tui_base.py
+++ b/src/ircplom/tui_base.py
@@ -184,7 +184,7 @@ class _HistoryWidget(_ScrollableWidget):
     @property
     def n_lines_unread(self) -> int:
         'How many new lines have been logged since last focus.'
-        return len(self._history) - self._last_read_idx_pos
+        return len(self._history) - self._last_read_idx_pos - 1
 
     def _scroll(self, up: bool = True) -> None:
         super()._scroll(up)