Just for information, i guess there will be posts about it as a Messenger Plus! bug.
If you use a-patch realesed today on the lastest 3555 version the Plus! and scripts button will be removed from the top bar (next to inbox / add contact / switch to full mode).
It have been reported to the a-patch creator on facebook i have seen so i guess it will be fixed. Guess that its not Plus! related.
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