I question whether its heretical because I'm not sure what dogma it denies.

.
I believe it either denies the dogma that 1) adultery is a mortal sin, or 2) someone in mortal sin can receive Holy Communion.

No, everyone doesn't acknowledge it, Ladislaus. There are people here who deny it. But that wasn't the main point there. There are 3 issues (1) Without Jurisdictional Bishops, it's already Check and Mate for 62 year SVism. You cannot pronounce judgment and so you have nowhere to go. (2) It is extremely unlikely even one single Pope will ever be a heretic, let alone 6 successive uncontested Papal candidates. (3) Third, you may claim you accept universal adherence in principle, but deny its application; yet the AER in 1965 applied it to the Pope. That means you're mistaken at least about those Popes Pope John XXIII and Pope Paul VI not having universal adherence.

.
A future true pope could condemn Bergoglio as a heretic and appoint bishops to fill all the sees currently vacant. Since Bergoglio is not a pope, he is not impeding the see of Peter (sorry Ladislaus). And we do not need jurisdictional bishops to elect a pope. In fact, Cajetan even discussed what the Church would do if all the jurisdictional bishops were unable to elect a pope, which implies that such a thing is not theoretically impossible. His answer was that the election of the pope would devolve to the whole Church.
.

(2) It is extremely unlikely even one single Pope will ever be a heretic, let alone 6 successive uncontested Papal candidates.

.
Um, are you trying to argue that Bergoglio is not a heretic? I'm a little confused where you're going with this.
.

(3) Third, you may claim you accept universal adherence in principle, but deny its application; yet the AER in 1965 applied it to the Pope. That means you're mistaken at least about those Popes Pope John XXIII and Pope Paul VI not having universal adherence.

.
There are a lot of intriguing historical questions that will have to be addressed about the late 1950's and into the 60's, probably by ancestors of ours breathing through gas masks in nuclear bunkers reading by the light of kerosene lamps and eating canned rations ... at least that's how I foresee the world looking like by the time the world has a pope again. In any case, yes, many SV's think John 23 was a true pope, based on the universal acceptance argument and the fact that there doesn't seem to be convincing, irrefutable proof that he taught heresy. The question of Paul VI is a profound mystery; possibly the most profound mystery to occur in 2,000 years. Was he a true pope when he was elected? Did he fall from office by espousing heresy? Despite so many theologians thinking this impossible? Did the whole Church truly accept him as pope, and does this prove he was at least initially a true pope? I don't have good answers for these questions, but since it's clear he promoted heresy in Vatican 2, that means at least he wasn't pope during much of his tenure.
.
But Paul VI is dead and gone. We have Francis now, and that should be our concern. And it is clear that he does not profess the Catholic Faith, and also that he is not universally and peacefully accepted as pope by people who truly believe in the Catholic Faith, including some people on this forum..
.
EDIT: shortened original quote from XavSem

AL wasn't about someone who just so happened to be ignorant about the Church's teaching, but about someone who is living objectively in a state of sin working it out with their confessor whether they could approach the Sacraments while continuing on in sɛҳuąƖ relations with someone who is not their spouse.  This contradicts the entire 2,000 year history of Church teaching on this subject going back to Sacred Scripture.  It is heretical.  Remember, the Church can teach dogmatically about either faith OR morals.

Again, I haven't read the docuмent, so maybe I'm way off  base here.

Maybe Francis is considering the following.

Man A and Woman B are brand new converts from Protestantism.  Man A had a previous marriage to Woman A.  Woman A committed adultery with Man C.  Man A (based on the Protestant theology of when divorce and remarriage is allowed) divorces her and marries Woman B.  Then the two of them are converting to Catholicism.  While they're in RCIA (or whatever) the priest informs them of the fact that divorce and remarriage isn't allowed.  The man has trouble accepting this because as far as he knows Woman B is in fact his wife, they've been together for years, and he can't fathom separating from her, he technically knows the Church says he has to but he doesn't really for the life of him understand how, etc.  

From what I understand Amoris Laetitia is saying objectively he's in sin, but since he presumably doesn't yet understand fully (even though he technically knows the Church teaches this, he doesn't understand why, etc.) he may be in venial sin, the Confessor can make a judgment that he is in fact in venial sin, and thus commune him.  Is that correct?

My gut reaction is to think this is scandalous, and that the judgment that he's only in venial sin is very likely to be wrong, but I'm not sure how its actual heresy, as it would be in the case where if for instance the Pope said these adulterous relationships aren't even objectively grave matter.  That is, unless you don't think subjective factors could *ever* reduce the gravity of a sin that is objectively grave to being subjectively not mortal, in which case that would make sense to say its heretical, but I've seen even trads say that such a thing is possible.  Again, I don't think they should be given communion, and I think to do so is scandalous, I'm just not sure if its an actual heresy.

But how can this not be mortal sin AFTER the person comes to know that it is?  Sure, these two Protestants may not have committed grave sin AT THE TIME that they initially divorced and remarried, and may not have been committing grave sin in having relations thereafter ... UNTIL they came to know that it is in fact grave sin.  From that moment on, what could possibly excuse them from grave sin?

Francis says that they can discern whether or not they truly mean well, somehow, even while continuing to commit grave sin.  So some kind of subjective disposition apparently can trump the obvious fact that they know it's grave sin and continue to do it.  Even John Paul II explicitly condemned this thinking.  Burke et al. in fact ask whether or not the teaching of John Paul II on this matter still stands.

John Paul II definitely held the line in terms of morality.  What he did, however, was to introduce subjectivism into the doctrinal realm.  So long as someone SINCERELY believes that what he believes is true, then that subjective disposition can in fact be supernatural faith.  Now, Francis takes this subjectivism into the realm of moral theology by claiming that if people are SINCERE (somehow) in having adulterous relations, then they do not commit grave sin.  So the recurring theme here with Vatican II is SUBJECTIVISM ... as +Williamson regularly points out.

I guess I was wondering if it was theoretically possible (even if unlikely) that something like extreme emotional blocks, lack of comprehension of the reasoning behind the Church's teaching, etc. could theoretically drop the culpability to the level where it might be venial.  I grant that this is kind of a stretch, and I really don't think its good reason to allow people to take communion, like if God really knows a person is in such a state than God can act accordingly, but I wasn't sure if speculation along such lines would actually be heretical.

It is typically said that three components are required for (subjective) mortal sin: grave matter, sufficient reflection, and consent of the will. The grave matter component is objective. Persons living in adultery in the way of spouses are in an objective state of grave sin. The subjective mortal sin and objective grave matter are different. That might still hold in the modern Church even after Amoris Laetitia[%].

Traditionally, the Church went by the objective matter in the external forum. Thus, someone who committed ѕυιcιdє was not buried in a church cemetery or with a church funeral, even though it could be argued that a successful ѕυιcιdє suggests psychological or other blocks to reflection or consent that might subjectively reduce the gravity of the sin.

In many areas - not just this one - the modern Church tends to make the situation in the external forum depend on the "totality of the circuмstances" or some such, which ends up blurring the subjective and the objective.

%. A statement of Pope Emeritus Benedict could be viewed as an answer to the Burke et al dubia concerning Amoris Laetitia. Not saying I agree with that.
https://www.thecatholicthing.org/2019/05/11/the-dubia-were-answered/

OK so basically this was my argument.  Given that, I agree with you, the Church *should* act based on the external forum, and thus it is *wrong* for them to try to act based on the subjective, it is *scandalous*.  But I'm not sure its actually *heretical*, as it would be if, for instance, AL was to say its not a grave sin at all.

it is *scandalous*.  But I'm not sure its actually *heretical*

Byzcat3000, it's written in Modernist language, just like V2.  They skirted the line of heresy, as usual, and (arguably) didn't cross it.  However, the docuмent is still GRAVELY wrong and GRAVELY sinful.  What does it matter if one goes to hell as a heretic or simply as a catholic in mortal sin?  The practical result is the same - the loss of Faith, the increase of immorality and the greater offense to God's laws (all of which are the Modernist's goals, because they are satan's henchmen, so they hate all things good - the Church, the faithful and God Himself).  Let's not get lost in the theological trees and miss the forest of evil this will lead to.

The Magisterium is AUTHENTIC and it is UNIVERSAL
The Magisterium can be utilized in an EXTRAORDINARY manner or in an ORDINARY manner
The Magisterium is infallible and unable to be mistaken

Ok, that is the strict definition which used to be used pre-1850s.  Using this criteria then, an encyclical like "Deus Caritas Est" from +Benedict would NOT be part of the magisterium because 1) he didn't teach anything authoritatively using his Apostolic authority, nor did he bind anyone to believe anything.  All he did was give a personal, theological opinion.
.
Since Vatican 1 defined infallibility, there has been a growing trend among theologians to expand the use of the term 'magisterium' to include all things coming forth from rome.  This new understanding means that such personal, theological opinions of the pope are now part of the "ordinary" magisterium, but aren't infallible, just fallible opinions.
.
It's a highly evolving area of theology because it has never been adequately explained.  The dawn of the defining of infallibilty at V1, only increased the questions as to what and when is the ordinary magisterium infallible.  Thus, there are all manner of explanations and terms used since then.