Fix the content navbar being hidden under the navbar when the window is narrow

[elia]

Summary

The new navbar doesn't support hiding and we shouldn't execute that code if it's in use.

cc @filippoliverani

Checklist

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[codecov]

Codecov Report

Merging #5423 (039fe9c) into main (bd404fe) will not change coverage.
Report is 5 commits behind head on main.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #5423   +/-   ##
=======================================
  Coverage   88.85%   88.85%           
=======================================
  Files         607      607           
  Lines       14748    14748           
=======================================
  Hits        13105    13105           
  Misses       1643     1643           

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[rainerdema]

Good catch! 👏

[github-actions]

💚 All backports created successfully

Status	Branch	Result
✅	v4.2

Questions ?

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