Viewing on mobile device, the Hamburger menu is invisible. However, if I click in that top right area, the menu drops down. Can anyone tell me where the code error is?
Thanks in advance,
There's nothing between the <button> </button> tags?
I don't use Bootstrap, least version 4.5, which is an old version, but recent versions included:
Between the <button> <span class="navbar-toggler-icon"></span> </button> tags.
That by its name, togger icon, should serve up your burger, tasty!