During development, there was a discussion that tags may get quite long in some languages (e.g. German), therefore should a Tag have 20 characters or more the font size should resize to fit screens in the responsive version.

The example is the "Energy Revolution" tag in Greek (see staging > https://greece.p4.greenpeace.org/greece/tag/energeia/) - looks alright in desktop but since it has 20 letters it gets cut.