New Installation - Navigation Menu and Table Styling

Greetings! I just installed Grav on my web server yesterday in an attempt to make a quick personal web site. I took the advice on the download page and installed v1.8.0-beta.3 - Admin v1.10.48. I tried another theme which looked promising, but decided to stick with Quark. Overall, this has been a great experience; however, I have encountered a couple of quirks. After searching for solutions, I decided to ask a question in the forum.

The first thing I encountered was unexpected behavior with the navigation menu. I created two folders: a primary navigation folder and then subfolders for content links.
However, when I click on the folder entries, the browser goes to a blank page.
I attempted to disable routing for the "pages" related to the folder entries; however, doing that just causes the browser to go to the first page contained within the folder instead of doing nothing. So, as an example, I have the following menu structure: Primary Folder -> Secondary Folder -> 01 - First Page | 02 - Second Page | 03 - Third Page. Clicking on Secondary Folder goes to 01 - First Page. Clicking on Primary Folder goes to the Secondary Folder page.

When I searched this problem, I found a few related forum posts which at first seemed promising. This is one: https://github.com/getgrav/grav-theme-antimatter/issues/103.
However, when I opened the file user/themes/quark/templates/partials/navigation.html.twig, its contents were completely different from what was described:

{% import 'macros/macros.html.twig' as macros %}

<ul {{ tree ? 'class="tree"' : '' }}>
    {{ macros.nav_loop(pages) }}
</ul>

There is no

 <a href="{{ p.url }}">

to modify. I considered just adding it in there, but I wasn't sure that would have the desired effect.

Additionally, I added a markdown table on one page. Within the admin portal editor's preview, the table appeared to be formatted adequately. However, when I visited the page in another browser, the table had no formatting at all. I also searched for some solutions to this problem, but I wasn't able to find anything that worked. This post, in particular, looked promising: /forum/support/add-striped-hover-tables-without-wrapping-tables-in-div-tags-quark-theme-t1070.

Unfortunately, wrapping the table in the same, or similar, <div> tag didn't do anything but cause the <div> tag text to appear on the page.

Are there some relatively simple solutions to these problems, or should I just use a different theme other than Quark?

I apologize if this has already been addressed elsewhere. It seemed like most of the discussions related to these problems were at least four years old.
Thanks for indulging the questions of a Grav newbie!

I also attempted to make the modification described in https://github.com/getgrav/grav-theme-antimatter/issues/103 to the /user/themes/quark/templates/macros/macros.html.twig file.

Original:

{% macro nav_loop(page) %}
  {% import _self as macros %}
  {% for p in page.children.visible %}
    {% set active_page = (p.active or p.activeChild) ? 'active' : '' %}
    <li>
      <a href="{{ p.url }}" class="{{ active_page }}">
        {{ p.menu }}
      </a>
      {% if p.children.visible.count > 0 %}
      <ul>
        {{ macros.nav_loop(p) }}
      </ul>
      {% endif %}
    </li>
  {% endfor %}
{% endmacro %}

Modified:

{% macro nav_loop(page) %}
  {% import _self as macros %}
  {% for p in page.children.visible %}
    {% set active_page = (p.active or p.activeChild) ? 'active' : '' %}
    <li>
      <a href="{% if p.routable %}{{ p.url }}{% else %}#{% endif %}" class="{{ active_page }}">
        {{ p.menu }}
      </a>
      {% if p.children.visible.count > 0 %}
      <ul>
        {{ macros.nav_loop(p) }}
      </ul>
      {% endif %}
    </li>
  {% endfor %}
{% endmacro %}

Unfortunately, the menu behavior persisted.

@belthasar:
Unfortunately, wrapping the table in the same, or similar, tag didn’t do anything but cause the tag text to appear on the page.

I seem to have resolved the problem regarding table formatting.
On another page I had used the following tags to put some text in a code block:

<pre><code>
     ...
</code></pre>

I looked at the page a few minutes ago and noticed that the tags were visible on the live page. Since editing that page last, I changed some configuration settings while attempting to get the table formatting to work. Specifically, I enabled all of the options in the Markdown settings.

One of these was "Escape markup," which I figured caused all HTML markup on pages to be escaped and appear as text. I disabled that, but left Markdown extras enabled, and the table now has the correct formatting.

Markdown configuration options:

The table formatting problem has been resolved with one of the previously mentioned work-arounds (linked above).

Now, if only I could resolve the navigation menu problem regarding linkable menu objects, I'd be all set.

Despite the information I found through web searches being four years old, or older, I was able to use the information to resolve the problems I originally described. This thread ended up being a few hours of self-rambling while I solved the problem; however, maybe it will be beneficial to other Grav users, at least for the confirmation that the seemingly old information is still applicable. If there's no value in this, then please feel free to delete this thread.

References:
/forum/themes-styling/quark-dropdown-menu-make-top-level-non-clickable-t7944
/forum/themes-styling/quark-open-publishing-top-level-drop-down-menu-how-to-make-non-clickable-t5044