In bootstrap 4.6 how to keep a collapsible menu open when user clicks to a new page

Question

I have a left side vertical nav menu with a couple sections that collapse submenus. How can I make it so that when the user navigates to a page from that submenu (#submenu1) that the menu is expanded on the next page?

<ul class="nav flex-column flex-nowrap overflow-hidden">
  <li class="nav-item">
    <a class="nav-link collapsed" href="#submenu1" data-toggle="collapse" data-target="#submenu1">
      <i class="fa-regular fa-user fa-fw"></i><span class="ml-1">Your Account</span>
    </a>
   
    <div class="collapse" id="submenu1" aria-expanded="false">
      <ul class="flex-column pl-2 nav">

Answer 1

Here you go...

You'll need to use a little bit of JavaScript/jQuery.

STEP 1

Add query string when user clicks on a link (source).

element.addEventListener('click', function(event) {
    // Stop the link from redirecting
    event.preventDefault();

    // Redirect instead with JavaScript
    window.location.href = element.href + '?menu=uncollapsed';
}, false);

STEP 2

Check query string value on a page load (source).

const params = new Proxy(new URLSearchParams(window.location.search), {
  get: (searchParams, prop) => searchParams.get(prop),
});

// Get the value of "menu" --> "https://example.com/?menu=uncollapsed"
let value = params.menu; // "uncollapsed"

STEP 3

If the value of "menu" is "uncollapsed" on a page load, then remove collapsed and add show Bootstrap classes.

$( document ).ready(function() {
    $('.navbar-toggler').removeClass('collapsed');
    $('.navbar-collapse').addClass('show');
});

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Note: These three steps will not work if you just copy-paste the code from my answer. You need to add a few minor things (e.g., if statement in the STEP 3), but this is the way I think you could make it work.