Changing fallback theme

I want to change the fallback theme of ubuntu to Yaru so I downloaded the Yaru icon pack from the git repo and pasted icon folder to .icon folder in home but my most application stop launching including gnome-terminal, files all extensions stop working. Thankfully xterm is working and I removed the folder I created and all apps function are back to normal. I don’t understand how changing the icon theme can affect the functionality of apps.

This site is for the co-ordination of the Ubuntu project(s), and not support.

Whilst you’re asking more about “why did this happen” instead of the normal “how do i fix” it still reads as a support request to me. I’m not a moderator on this site, but if a moderator agrees with me, you may find this question closed.

For Ubuntu Support options, please have a look at https://community.ubuntu.com/t/finding-help/712 (where to me your question would better fit a Ubuntu.forums or ask.Ubuntu question)