diff --git a/addons/website_slides/models/slide_channel.py b/addons/website_slides/models/slide_channel.py
index 3dfba4e7576..30aee951c11 100644
--- a/addons/website_slides/models/slide_channel.py
+++ b/addons/website_slides/models/slide_channel.py
@@ -338,7 +338,7 @@ class Channel(models.Model):
     def action_channel_invite(self):
         self.ensure_one()
 
-        if self.visibility != 'invite':
+        if self.enroll != 'invite':
             raise UserError(_("You cannot send invitations for channels that are not set as 'invite'."))
 
         template = self.env.ref('website_slides.mail_template_slide_channel_invite', raise_if_not_found=False)
diff --git a/addons/website_slides/models/slide_slide.py b/addons/website_slides/models/slide_slide.py
index 0ab75feec59..9ca2eff8adb 100644
--- a/addons/website_slides/models/slide_slide.py
+++ b/addons/website_slides/models/slide_slide.py
@@ -105,7 +105,7 @@ class Slide(models.Model):
     category_id = fields.Many2one('slide.category', string="Category", domain="[('channel_id', '=', channel_id)]")
     tag_ids = fields.Many2many('slide.tag', 'rel_slide_tag', 'slide_id', 'tag_id', string='Tags')
     access_token = fields.Char("Security Token", copy=False, default=_default_access_token)
-    is_preview = fields.Boolean('Always visible', default=False)
+    is_preview = fields.Boolean('Is Preview', default=False, help="The course is accessible by anyone : the users don't need to join the channel to access the content of the course.")
     completion_time = fields.Float('# Hours', default=1, digits=(10, 4))
     # subscribers
     partner_ids = fields.Many2many('res.partner', 'slide_slide_partner', 'slide_id', 'partner_id',