Hi and sorry for this late reply! I just had too much urgent work recently and also the holidays and I wasn’t able to check the forums.
Yes, that’s a side effect of the automatically added carets – they are added ondomready when the menus are initialized and that’s why the effect can be noticed on page reload. You can disable this feature if you like and add manually Bootstrap carets to the items directly in the source. Here I’ve explained how you can disable the automatically added carets: