InterruptAlert is a custom add-on that was created for me by someone else which alerts me if my target is casting a spell. It's definitely not one of those add-ons that announces to everyone that they interrupted something -- I really dislike those spammy add-ons.
I haven't used JAMBA since sometime during WotLK. Props to Jafula for creating it and maintaining it, but I just feel that 1) it doesn't do anything for me that I can't really already do myself, and 2) it doesn't fit into my UI anywhere.
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