diff --git a/lua/telescope/command.lua b/lua/telescope/command.lua
index 0da84baca8..63d299ab58 100644
--- a/lua/telescope/command.lua
+++ b/lua/telescope/command.lua
@@ -112,6 +112,9 @@ command.convert_user_opts = function(user_opts)
             user_opts[key] = eval
           else
             -- otherwise return nil (allows split check later)
+            -- BUG: this doesn't allow things like `preview=false`, where an
+            -- option supports other types other than the default type
+            -- (`preview` has a default type of table)
             user_opts[key] = nil
           end
         end
diff --git a/lua/telescope/previewers/buffer_previewer.lua b/lua/telescope/previewers/buffer_previewer.lua
index ee12453bcb..77322d74ec 100644
--- a/lua/telescope/previewers/buffer_previewer.lua
+++ b/lua/telescope/previewers/buffer_previewer.lua
@@ -36,6 +36,9 @@ local function defaulter(f, default_opts)
   default_opts = default_opts or {}
   return {
     new = function(opts)
+      if opts.preview == false then
+        return false
+      end
       if conf.preview == false and not opts.preview then
         return false
       end