Current editor's modification state has changed
        --> change tab title depending on new modification state
        --> enable/disable save/save all actions

def modification_changed(self, state=None, index=None, editor_id=None):
        """
        Current editor's modification state has changed
        --> change tab title depending on new modification state
        --> enable/disable save/save all actions
        """
        if editor_id is not None:
            for index, _finfo in enumerate(self.data):
                if id(_finfo.editor) == editor_id:
                    break
        # This must be done before refreshing save/save all actions:
        # (otherwise Save/Save all actions will always be enabled)
        self.opened_files_list_changed.emit()
        # --
        if index is None:
            index = self.get_stack_index()
        if index == -1:
            return
        finfo = self.data[index]
        if state is None:
            state = finfo.editor.document().isModified() or finfo.newly_created
        self.set_stack_title(index, state)
        # Toggle save/save all actions state
        self.save_action.setEnabled(state)
        self.refresh_save_all_action.emit()
        # Refreshing eol mode
        eol_chars = finfo.editor.get_line_separator()
        self.refresh_eol_chars(eol_chars)
        self.stack_history.refresh()