vteaccess.c contains inefficient and hard-to-read loops like

        /* Find the first byte that scrolled off. */
        for (i = 0; i < priv->snapshot_attributes->len; i++) { 
                attr = g_array_index(priv->snapshot_attributes,
                                struct _VteCharAttributes,
                                i);
                if (attr.row >= delta + row_count - howmuch) {
                        break;
                }
        }

whereas there's a snapshot_linebreaks array, getting the value of "i" should be a direct lookup to this array, shouldn't it?