// tok must come from htmlTok
// returns all container tags found (including content) as CNC
// should be OK for both HTML and XML
static LL findContainerTagWithClass(L tok, S tag, S className) {
ret filter(findContainerTag(tok, tag), t -> tagHasClass(t, className));
}
static LL findContainerTagWithClass(S html, S tag, S className) {
ret findContainerTagWithClass(htmlTok(html), tag, className);
}