📚 Is Spotify dropping "support" for the semi-official Linux client?

So I’ve just recently got a mail from Spotify that they are gonna be phasing out support for older desktop clients which I apparently have one of (according to the email). But they didn’t specify which client and I have Spotify also installed on a Mac as well as Windows. My guess is that it’s the Linux client because of it’s not really official status. I don’t know if it has gotten any updates or not in recent time.

Also isn’t it just some sort of web app in an application container of sorts?

Please Spotify why don’t you specify what desktop client you mean. Not everybody has just one desktop/laptop.