Messages du forum envoyés par e-mail grisés en mode sombre sur certains forums Discourse

Je peux reproduire le problème en utilisant l’application Web Outlook sur Microsoft Edge (version 106.0.1370.47 (build officiel) (64 bits)), Firefox 106.0.1 (64 bits) et Chrome (version 106.0.5249.119 (build officiel) (64 bits)) sous Windows 10 Enterprise, version 20H2.

Paramètres Windows 10 > Personnalisation > Couleurs >
Puis, soit :
Choisir votre couleur : Personnalisé.
Choisir votre mode d’application par défaut : Sombre.
ou :
Choisir votre couleur : Sombre.

Application Web Outlook > Paramètres > Mode sombre : Désactivé.

Cela semble être dû aux propriétés de couleur dans ce style CSS extrait d’un e-mail de nouvelle version (à titre d’exemple) ci-dessous ? :

<div class="rps_735d"><div dir="ltr" style="line-height:1.4; text-align:left"><p>Hooray, a new version of <a href="https://www.discourse.org" target="_blank" rel="noopener nofollow ugc noreferrer" data-auth="NotApplicable" style="text-decoration:none; font-weight:bold; color:#006699" data-safelink="true" data-linkindex="0"><span data-markjs="true" class="mark95gsb08l7" style="background-color: rgb(255, 241, 0); color: black;" data-ogac="" data-ogab="" data-ogsc="" data-ogsb="">Discourse</span></a> is available!</p><p>Your version: 2.9.0.beta9<br aria-hidden="true">New version: <strong>2.9.0.beta10</strong></p><ul style="margin:0 0 0 10px; padding:0 0 0 20px"><li style="padding-bottom:10px"><p>Upgrade using our easy <strong><a href="https://forum.step.org/admin/upgrade" target="_blank" rel="noopener noreferrer" data-auth="NotApplicable" style="text-decoration:none; font-weight:bold; color:#006699" data-safelink="true" data-linkindex="1">one-click browser upgrade</a></strong></p></li><li style="padding-bottom:10px"><p>See what’s new in the <a href="https://meta.discourse.org/tag/release-notes" target="_blank" rel="noopener nofollow ugc noreferrer" data-auth="NotApplicable" style="text-decoration:none; font-weight:bold; color:#006699" data-safelink="true" data-linkindex="2">release notes</a> or view the <a href="https://github.com/discourse/discourse/commits/main" target="_blank" rel="noopener nofollow ugc noreferrer" data-auth="NotApplicable" style="text-decoration:none; font-weight:bold; color:#006699" data-safelink="true" data-linkindex="3">raw GitHub changelog</a></p></li><li style="padding-bottom:10px"><p>Visit <a href="https://meta.discourse.org" target="_blank" rel="noopener nofollow ugc noreferrer" data-auth="NotApplicable" style="text-decoration:none; font-weight:bold; color:#006699" data-safelink="true" data-linkindex="4">meta.<span data-markjs="true" class="mark95gsb08l7" style="background-color: rgb(255, 241, 0); color: black;" data-ogac="" data-ogab="" data-ogsc="" data-ogsb="">discourse</span>.org</a> for news, discussion, and support for <span data-markjs="true" class="mark95gsb08l7" style="background-color: rgb(255, 241, 0); color: black;" data-ogac="" data-ogab="" data-ogsc="" data-ogsb="">Discourse</span></p></li></ul><h3 style="margin:30px 0 10px"><a name="x_release-notes-1" href="#x_release-notes-1" style="text-decoration:none; font-weight:bold; color:#006699" data-safelink="true" data-linkindex="5"></a>Release notes</h3><p>Read about the release here:</p><p><a href="https://meta.discourse.org/t/2-9-0-beta10-sidebar-new-notification-menu-security-fixes-and-more/239858" target="_blank" rel="noopener nofollow ugc noreferrer" data-auth="NotApplicable" style="text-decoration:none; font-weight:bold; color:#006699" data-safelink="true" data-linkindex="6">https://meta.<span data-markjs="true" class="mark95gsb08l7" style="background-color: rgb(255, 241, 0); color: black;" data-ogac="" data-ogab="" data-ogsc="" data-ogsb="">discourse</span>.org/t/2-9-0-beta10-sidebar-new-notification-menu-security-fixes-and-more/239858</a></p><p>This release includes security fixes, so please update as soon as possible.</p><div style="display:none; white-space:nowrap; font:15px courier; line-height:0"> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </div><style>
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Une solution de contournement en attendant serait de suggérer à l'utilisateur d'activer le mode sombre dans les paramètres de l'application Web Outlook...