In tags for 1426B - Symmetric Matrix, there are two Implementation tag, how is it possible :/ ??

Also when you look at the problemset, there is only one Implementation tag for this problem, but when you go to the problem page, you see 2 of them

I don't know if its still the same when you are reading this blog, but this is the screenshot:

Some another example on 1426A - Floor Number:

Maybe their implementation is too hard :)

Can i do the same thing by opening multiple tabs and add them at the same time ?? I mean just select the tag in multiple tabs and submit them after selecting the tags ??