I have ignored and hid programming-challenge so I won't get to see them and get spoilers.
I had to ignore the chatbot "Captain Obvious" for now, but I don't want to do that because I want to know the questions that are being posted while I'm in The 2nd Monitor.
Any idea on how to fix this? Is it even fixable (limitations of SE chat)?
This is currently not really "fixable" no. Either the chatbot (known in most other chat rooms simply as "Stack Exchange") informs about all questions, or about no questions. Likewise, it either informs everyone, or no one.
The only possible solution to filter questions is to use a different feed which posts only questions in a specific tag for example. Creating such a feed with a filter that filters away one specific tag is not a very easy task, and there has been problems getting certain feeds to work at all. Then again, some users want to see those questions that you want to filter away.
As a lot of people hang out in The 2nd Monitor, this is the fastest way to discover off-topic questions. It is usually indicated by pinging Captain Obvious and commenting about the question. So Captain Obvious should definitely stay.
Really. The biggest spoiler comes when you click on the question and actually read it. Especially if you would read the answers to the questions. Unless you consider simply knowing about what the question is about as a spoiler, then you are in trouble. (For example if you are informed that Project Euler #1 is about summing numbers that are multiples of 3 and 5).
There's two different ways to ignore someone in chat:
The first works using simple Javascript. As soon as you click the button, the messages from the user magically disappear. (This doesn't help in transcript)
The hidden messages will appear again, as soon as you reload the chat.
The second adds the user to your Ignore-List. This also hides messages of this user from transcript. You can see the ignored users in your chat preferences:
