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I have a few watched tags I would like to pay attention to. But the problem is when I'm going through StackExchange questions, sometimes I have to double check to see whether I have subscribed to that tag or not. This a problem when you don't remember all tags that you're subscribed. This could be easily avoided if we can easily identity watched tags from other tags.
However, this should not be aggressive or distractive. Users must always be able to focus on the questions.
This is an example...
Normal (without the feature): Watched Tag: password-management
Highlight (after feature implemented): Watched Tag: password-management