Vue warn : cannot find element #app event though there's already id app

Hi guys
I’m learning laravel right now from freecodecamp youtube channel, so counter some issue when trying to make component button but somehow my follow button disappeared, so open the console and always get this warning idk why?
Here’s the video I’m talking about, Here
You can see at 3:24:24 he make separate button and he can run it perfectly.

ok i had the same issue but i resolved it. You have to move your script tag at the bottom of your body tag in app.js file, after @yield(‘content’).

<main class="py-4">

            @yield('content')

        </main>
    </div>
    <script src="{{ asset('js/app.js') }}"></script>

</body>

it should look like above in app.js file

Sorry for late reply, you mean script in app.blade?
I move it at the bottom like you said, but it got new error instead, it said

[Vue warn]: Error compiling template:

v-slot can only be used on components or <template>.

3  |              <div class="container">
4  |                  <a class="navbar-brand d-flex" href="http://127.0.0.1:8000">
5  |                      <div><img src="/svg/freecodecamp.svg" style="height : 20px;" border-right:="" 1px="" solid="" #333="" class="pr-3"></div>
   |                                                                                                                    ^^^^^^^
6  |                      <div class="pl-3 pt-1">TestGram</div>
7  |                  </a>

(found in <Root>) app.js:37765:15
    warn http://127.0.0.1:8000/js/app.js:37765
    compileToFunctions http://127.0.0.1:8000/js/app.js:48812
    compileToFunctions http://127.0.0.1:8000/js/app.js:48811
    $mount http://127.0.0.1:8000/js/app.js:49035
    _init http://127.0.0.1:8000/js/app.js:42137
    Vue http://127.0.0.1:8000/js/app.js:42203
    js http://127.0.0.1:8000/js/app.js:49189
    __webpack_require__ http://127.0.0.1:8000/js/app.js:20
    0 http://127.0.0.1:8000/js/app.js:49340
    __webpack_require__ http://127.0.0.1:8000/js/app.js:20
    <anonymous> http://127.0.0.1:8000/js/app.js:84
    <anonymous> http://127.0.0.1:8000/js/app.js:87

And the button still disappeared.

Looks like I was messing up my app.blade

<div><img src="/svg/freecodecamp.svg" style="height : 20px; border-right:1px solid #333"  class="pr-3"></div>

That border-right was supposed to be inside the quote and now it work, also I tried to put back script on top, and it’s not working, so you right I need to put the script at bottom and now the button is back. Thanks man.