JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <div class="common true">1111</div>
    <div class="common">2222</div>
    <div class="common true">3333</div>
    <div class="common true">4444</div>
    <div class="common true">5555</div>
    <div class="common true">6666</div>
    <div class="common true">7777</div>
    <div class="common">8888</div>
</div>

CSS

.common.true{
    display: block;
    border-top: 1px solid;
}
.common{
    display: none;
}
div[class~='.true']:last-of-type{
    border-top: none;
}

JavaScript

$(".true").last().css( "border-top", "none" );