This is a...
Problem:
This is a screenshot on Safari 11.1 / macOS 10.13.4, It works fine on latest Google Chrome. I've seen this maybe for a year. I tried to fix this several times but didn't make it.

Proposed Solution:
Page to Update:
Basically all pages of https://kubernetes.io
/kind bug
/sig ui
/remove-sig ui
/sig docs
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/help
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Still a bug? shall I work on this? @idealhack
@Sai-Adarsh I believe so, feel free to take it :)
/priority backlog
Is that OK?
I thought bugs shouldn't be backlog? this is a long-existing bug though.
thanks for triaging issues in this repo.
Still an issue

/assign I'll try to fix it.
Thanks for looking at this @furukawa3! 馃帀 In order for the bot to recognize commands each one has to be on a new line. I took the liberty of assigning you
/assign @furukawa3
/lifecycle active
Oops!! Thanks @hvaara for assigning :)
1 question. Could you tell me what kind of browser does k8s document page support? Currently, I try to fix Safari first. ( I also found the similar error with IE 11.0.146. Only "language" Sub-nav was wrong. )

@furukawa3 san, thanks for looking at this!
From what I can confirm, this sub-sav works with Chrome and FireFox, but not work with Safari.
Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.
If this issue is safe to close now please do so with /close.
Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale
/lifecycle frozen
it seems this was fixed after the theme update: https://kubernetes.io/blog/2020/06/better-docs-ux-with-docsy/