Is upgrade from 1.6.6.3 to current version safe?

We’ve inherited an old wordpress site that has been unmaintained for some time. I’ve been going through the plugins one-by-one and trying to get them up to date. The site is currently using Types version 1.6.6.3. Is there any known breakage that would be caused if I update to the current version or is it just security updates and bug fixes between 1.6.x and 1.8.x?

I’ll do a backup of course, I’d just like to know ahead of time if this is likely to cause something important to stop working.

https://ww.wp.xz.cn/plugins/types/