<!-- Stripped down, this is what your code is outputting: -->

<div class="fw-row">
	<div class="fw-col-xs-12">
		<strong>
		
			<div id="ld_categorydropdown">[FORM ETC]</div>
			
			<div class="ld_course_grid col-sm-6 col-md-4">
				<article id="post-70" class="thumbnail course post-70 ...">
				</article><!-- #post-## -->
			</div>
			<div class="ld_course_grid col-sm-6 col-md-4">
				<article id="post-13" class="thumbnail course post-13 ...">
				</article><!-- #post-## -->
			</div>
	
		</strong>
	</div>
</div>

<!-- This is what it should look like instead: -->

<div class="fw-row">
	<div class="fw-col-xs-12">	

		<div id="ld_categorydropdown">[FORM ETC]</div>
		
		<div class="row">
			<div class="ld_course_grid col-sm-6 col-md-4">
				<article id="post-70" class="thumbnail course post-70 ...">
				</article><!-- #post-## -->
			</div>
			<div class="ld_course_grid col-sm-6 col-md-4">
				<article id="post-13" class="thumbnail course post-13 ...">
				</article><!-- #post-## -->
			</div>
		</div><!-- end new 'row' -->
		
	</div>
</div>

I'm using the learndash shortcode:
[ld_course_list categoryselector=true col=3]

The HTML it outputs is missing a div with class=row. When you're using Bootstrap, you need a "row" div if you want to put col divs inside of other col divs. You also have everything inside of a <strong> tag, which is clearly an error.

What you should do is a) rid of the <strong> tag, and b) you should add a <div> after the ld_categorydropdown div that closes where the </strong> currently is.

You might ask why I care. I care because I'm trying to style this thing, and the boxes/columns don't line up properly if they aren't in a "row".

LearnDash errors with Bootstrap CSS

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