Gift modal appears in reader mode output for lemonde.fr articles

Via https://bugzilla.mozilla.org/show_bug.cgi?id=1922931 .

HTML of the modal looks like this:

<div id="js-modal-gifted-url" class="article__gift-modal"> <div class="article__gift-modal__overlay"></div> <div class="article__gift-modal__content"> <div class="article__gift-modal__title"><span class="article__gift-modal__logo icon__gift"></span>Cet article vous est offert</div> <div class="article__gift-modal__text">Pour lire gratuitement cet article réservé aux abonnés, connectez-vous</div> <a class="lmd-btn lmd-btn--primary lmd-btn--l lmd-btn--fullwidth js_modal_login" href="https://secure.lemonde.fr/sfuser/connexion?gift=true">Se connecter</a> <div class="article__gift-modal__text article__gift-modal__text--no-margin lmd-typo--text-center"> Vous n'êtes pas inscrit sur Le Monde ? <br> <a class="article__gift-modal__link js_modal_login" href="https://secure.lemonde.fr/sfuser/register?gift=true">Inscrivez-vous gratuitement</a> </div> </div> </div>

The article__gift-modal class gets display: none in some CSS but that does not make it into readability's determinations of what to do.

Start by tracing how Readability handles the supplied lemonde.fr HTML and whether the article__gift-modal element reaches the output despite its CSS display:none rule. Use the provided modal markup as the reproduction case; done means the gift modal is excluded from reader mode output without removing article content.