Mint-Y Style Controls don't render properly

[Tmpod]

Hey everyone!
So, 2 months or so ago, my brother bought a new PC and I got his "old" one. He had Windows and Linux Mint and he didn't want to go through the assle of installing both OSes again, so I just created an account from me in each one.
The thing is, this is Mint 17.1 Cinnamon (64-bit) and Mint-Y is from 18 (as far as I understand). I used to have Mint-Y-Dark in Mint xfce on my crappy computer and so I wanted to have it on this computer too. I got the themes from the built-in "theme store" (ig we can call it that). Everything worked wonder except the controls part. This is what it looks like with any Mint-Y controls (and this is what it looks with a Mint-X theme )

Does anyone know what is causing this and what I could do to fix this issue?
If you need anymore details I would be more than happy to give you those!

Thanks in advance,
Tmpod

[smurphos]

Update to Mint 18 or later. Mint-Y was built for GTK 3.18 (Mint 18.x version) or GTK 3.22 (Mint 19 version). Mint 17.x I think uses GTK 3.14.

[Tmpod]

My problem is that I can't really update Mint because the PC isnt all mine... Could I update the GTK instead?

[smurphos]

You could try updating GTK version but that may well break more than it fixes. Having checked it's actually GTK 3.10 in Mint 17.x. Your applications will have been compiled against GTK 3.10 and may not display correctly with GTK 3.18 or higher. If you want to go down this road - and I wouldn't recommend it - the package needed is here - https://packages.ubuntu.com/xenial/libgtk-3-0 - but you are likely to need to download and install additional packages from the xenial repos to meet it's dependencies. Things could quickly get messy.

If updating the Mint install is not an option then the other safe route is trying to fix up the Mint-Y theme to work with GTK 3.10. The place to start is GTK related error messages in ~/.xsession-errors. That should show you what lines of code the the gtk.css files in the theme your version of GTK doesn't like and which need to be modified. I've no idea how straightforward or not this would be trying to make a GTK 3.18 theme work with GTK 3.10.

I'm away from home and my Mint machine at the moment so can't have a look at this myself, but if you try and get stuck post back and I'll have a look at it in a week or two once I am home again.

[Tmpod]

You could try updating GTK version but that may well break more than it fixes. Having checked it's actually GTK 3.10 in Mint 17.x. Your applications will have been compiled against GTK 3.10 and may not display correctly with GTK 3.18 or higher. If you want to go down this road - and I wouldn't recommend it - the package needed is here - https://packages.ubuntu.com/xenial/libgtk-3-0 - but you are likely to need to download and install additional packages from the xenial repos to meet it's dependencies. Things could quickly get messy.

If updating the Mint install is not an option then the other safe route is trying to fix up the Mint-Y theme to work with GTK 3.10. The place to start is GTK related error messages in ~/.xsession-errors. That should show you what lines of code the the gtk.css files in the theme your version of GTK doesn't like and which need to be modified. I've no idea how straightforward or not this would be trying to make a GTK 3.18 theme work with GTK 3.10.

I'm away from home and my Mint machine at the moment so can't have a look at this myself, but if you try and get stuck post back and I'll have a look at it in a week or two once I am home again.

Hmmm... Idk if I want to go down that path... I think I'm gonna try to convince the other user to update Mint first. If he really doesn't want to, I guess I could try to modify the theme as you suggested. Thanks a lot for your answer!