The issue exists in production and betalabs.

Steps:

1. From any page, click on 'Preferences' link in the upper navigation bar.
2. Make some changes in any section but not 'Beta features'.
3. Navigate away to a different page
4. Click on 'Beta' link (<a href="/wiki/Special:Preferences#mw-prefsection-betafeatures" title="Beta features">Beta</a>) - you will be redirected to the section of Preferences where you made changes.
5. When you click on Preferences and attempt to go to 'Beta features' via clicking on the link <a id="preftab-betafeatures" role="tab" href="#mw-prefsection-betafeatures" aria-controls="mw-prefsection-betafeatures" aria-selected="false" tabindex="-1">Beta features</a>, nothing will happen.

Another section link has to be clicked so the 'Beta features' link starts working again.