Buttons don’t have accesible names

Hi!

I’m getting an error on PageSpeed Insights, on the “Accessibility” audit, stating “buttons don’t have accessible names”. This is shown in regards to the button that triggers the menu opening:

<button type="button"?class="menu-mobile-toggle item-button is-size-desktop-medium is-size-tablet-medium is-size-mobile-small">

Could you take a look at the cause of this error? Thanks!

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