Baloo I don't have messenger downloaded even and mine shows the C (copyright) symbol at the bottom of every page without text next to it. The only way you see text is if the symbol is clicked on then you will see 2018 Company. I don't think it's a conflict with messenger.
Additional indications. I have this problem with Protean, Decorus. So, I think the problem really comes from messenger + popup because I just installed "Lucid" and the key remains ok with or without messenger.