[Bug]: referenceButtons are undefined

[AmasiaNalbandian]

Sometimes reference buttons is undefined, in which case we get errors in the console. We should add an optional chain for this logic.
see here:

material-dashboard/assets/js/material-dashboard.js

Line 626 in 6671668

if (referenceButtons.classList.contains('active') && referenceButtons.getAttribute('data-class') === 'bg-transparent') {

See issue related here: Seneca-CDOT/telescope#2691

[AmasiaNalbandian]

Please feel free to assign this to me - I'd be happy to add it in,

[github-actions]

@AmasiaNalbandian this issue was automatically closed because it did not follow the bellow rules:

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