diff --git a/mail/js/app.js b/mail/js/app.js
index 9ca2b9193f..d3cf24a5f2 100644
--- a/mail/js/app.js
+++ b/mail/js/app.js
@@ -2438,10 +2438,18 @@ app.classes.mail = AppJS.extend(
 		// we can NOT query global object manager for this.nm_index="nm", as we might not get the one from mail,
 		// if other tabs are open, we have to query for obj_manager for "mail" and then it's child with id "nm"
 		var obj_manager = egw_getObjectManager(this.appname).getObjectById(this.nm_index);
+		let tree = this.et2.getWidgetById('nm[foldertree]');
 		var that = this;
 		var rvMain = false;
 		if ((obj_manager && _elems.length>1 && obj_manager.getAllSelected() && !_action.paste) || _action.id=='readall')
 		{
+			// Avoid possibly doing select all action on not desired mailbox e.g. INBOX
+			for (let n=0;n<_elems.length;n++)
+			{
+				// drop the action if there's a mixedup mailbox found in the selected messages
+				if (atob(_elems[n].id.split("::")[3]) != tree.getSelectedNode().id.split("::")[1]) return;
+			}
+
 			if (_confirm)
 			{
 				var buttons = [