Using Google API explorer, I found out the id of a specific event in my calendar:
_6tlnaqrle5p6cpb4dhmj4phpehomip3975p68qj569gmaqj669knadrjelo68eb161gmcdjgcdh6os1kdtk3cpblcso66dhmehim6qr7csr6e
I read an explanation here:
Events | Google Calendar | Google for Developers
characters allowed in the ID are those used in base32hex encoding, i.e. lowercase letters a-v and digits 0-9, see section 3.1.2 in RFC2938
So, I see that the underscore appearing in the obtained id doesn't match that specification.
What's the issue here ? Is the id encoded using a different system ?