In what seems a regression, the "edit description" link is shown in blue. That makes it too prominent.
In the screenshot below you can see that a user edited the page description to participate in the conversation (having the "edit description" link as the most prominent actionable item may have contributed to the confusion):
{F2612670}
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Copied from duplicate T145773
That label is too visible. Some users misunderstood what it is for, and post messages on board description instead of creating a topic. Or it is just vandalism.
Examples:
* https://fr.wikipedia.org/w/index.php?title=Discussion_utilisateur:Ash_Crow&action=compare-header-revisions&header_newRevision=tblzfs1txnad8z1t
* https://fr.wikipedia.org/w/index.php?title=Wikip%C3%A9dia:Forum_des_nouveaux/Flow&action=compare-header-revisions&header_newRevision=sw8haxvpec5shvc3
* https://fr.wikipedia.org/w/index.php?title=Wikip%C3%A9dia:Forum_des_nouveaux/Flow&action=compare-header-revisions&header_newRevision=sw3c0gccpkbkutkp
* https://fr.wikipedia.org/w/index.php?title=Discussion_Wikip%C3%A9dia:Flow&action=compare-header-revisions&header_newRevision=tatt8q48nte7io99