Icons look jittery at lower sizes

[codecat]

Acknowledgement

• I am aware that this issue will not be worked on unless other maintainers take over the project.

Issue body

For me, icons look a bit "jittery" at smaller sizes. I don't know if this is a font issue or just an issue with my page styles:

It looks like Font Awesome 4.7 does not suffer from this issue. 🤔