Galaxy S6, with Verizon's recent Android Nougat update: This bug is similar to one already reported by someone else, except I notice it most when using speech to text rather than when typing a message. When using speech to text to compose a message, typically certain translated words or phrases are shown underlined because the Google speech to text engine has alternatives to suggest. You can tap on the underlined word and a menu pops up offering a number of alternates that can be selected by tapping on them. Since the Nougat update, this pop up menu displays as a very dark gray background and the font is using black text, so the words it displays are virtually unreadable.
I do NOT see this problem when using the same speech to text function with other apps that present a keyboard, such as WhatsApp or Google Calendar. Those apps still display the suggested words popup menu as black text on a white background. So the bug seems localized to Message+, and only since Nougat or perhaps a Message+ update that coincided with Nougat. For me this bug makes Message+ unusable as I tend to use speech to text all the time.
This problem is still present in the latest update to Messages that I installed on 5/25/2017, version 6.4.201.
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