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Here is the problem. I have a long-term visa (I live and work in Germany and I'm married). I want to visit London (to be specific, I am from Tunisia).
I heard that having a long-term visa for a European country can make it easier for me to apply for a UK visa (as I saw, the visa is required in my case).
I don't know how I should apply for this visa, and to use my European visa to facilitate the steps.