mutt_clear_threads (ctx);
static void maildir_update_tables (CONTEXT *ctx, int *index_hint){  short old_sort;  int old_count;  int i, j;    if (Sort != SORT_ORDER)  {    old_sort = Sort;    Sort = SORT_ORDER;    mutt_sort_headers (ctx, 1);    Sort = old_sort;  }    old_count = ctx->msgcount;  for (i = 0, j = 0; i < old_count; i++)  {    if (ctx->hdrs[i]->active && index_hint && *index_hint == i)      *index_hint = j;        if (ctx->hdrs[i]->active)      ctx->hdrs[i]->index = j++;  }  mx_update_tables (ctx, 0);}