I practice questions in Codeforces Problemset by hiding tags for unsolved problems. However, sometimes it turns out to be a April Fools question and sometimes after spending 30-40 mins in a question I find that what was a Kotlin only problem, then I re-write my whole approach in Java then download Jetbrains IDE to convert that to Kotlin, and most of times I don't get AC as I don't know Java well. These things wastes time!
Currently in CF, we can see problems for a particular tag using the filter box in right side, but there is no option to remove problems for a particular tag (*special problem in this case) using the filter.
I request the admins to add this feature.