Bug with Assigning Filter Using Labels

I think I discovered a bug with how the assignment of labels works within the filter settings.

Let's say my Zoho address is 123@zoho.com and I have a label "Work" created for this account. Now if I set up a POP3 account (e.g. 123@yahoo.com) and go to the filter settings for this Yahoo account, I will get an error message when I try to create a new filter with the same name ("Work" in this case), even though the filter with such a name still does not exist for this account.

I basically need to go to the Labels setting first and create the label there, and then go back to the Filter setting and assign the created label. I couldn't do both, creating the new label and assigning it in the filter, under the Filter setting when the label already exists in another account. I get an error telling me that "The Label Already Exists."

Even though the labels are supposed to be account specific, they seem to be commonly shared across different accounts under the filter settings.