Messages Address Bubble Colors
When you enter an email address or type one into the address field in Messages, the software does a quick behind-the-scenes check. Messages tries to determine if the address is associated with an active iCloud account. As you accept or paste in an address, you might notice that it always briefly lights up black text within a blue lozenge. If the address isn’t connected, the background changes from blue to red. This sometimes happens so quickly you don’t see it move from blue to red.
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As shown in the lifecycle figure above, sometimes you will see a blue lozenge for a match—cached? preliminary?—but once you click in the message field, and shifts to green text!
More confusingly, even if you type in a non-iCloud-connected email address and the contact with which the address is associated also has an iCloud-hooked-up address, Messages forces the use of the iCloud-linked address! I haven’t found a way to force use of a non-iCloud address without removing that email from the contact card.
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I found frustrating just the sheer number of things that lacked information at support.apple.com or which had “drug interaction”-like problems where features conflicted with each other.
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