Error when displaying the sidebar with the list of LifterLMS lessons

I’m using the “Course Syllabus” widget in the body of the page to display a list of lessons on the course page. But after adding content to the lesson, its name in the list disappears.

At the same time, if you display the sidebar in the right place (for example, use the page template with the right sidebar), then the lessons are displayed correctly.
Checked with disabling all plugins except Lifter LMS.
In any other theme with LLMS support, the problem disappears. That is, the conflict occurs only when the sidebar is displayed in the body of the course and only with the WhiteDot theme.

Sample code before content filling the lesson:

<ul class="llms-lesson ">
<li>
<span class="llms-lesson-complete ">
<i class="fa fa-check-circle">
<::before></::before>
</i>
</span>
<span class="lesson-title ">
<a href="https://novy.czechkat.com/lesson/audiokurz7-1/">
7.1. Kapr na dva zp?soby
<::after></::after>
</a>
</span>
</li>
</ul>

Sample code after content filling the lesson:

<ul class="llms-lesson ">
<li>
<span class="llms-lesson-complete ">
<i class="fa fa-check-circle">
<::before></::before>
</i>
</span>
<span class="lesson-title ">
<a href="https://novy.czechkat.com/lesson/audiokurz7-1/">
<::after></::after>
</a>
</span>
</li>
</ul>

LifterLMS v7.0.0
WordPress v6.0.2
Theme childe for WhiteDot v1.2.3 and WhiteDot v1.2.3 (the problem is both when using a child theme, there is also a parent theme)

What can I do to correct the situation? What could be causing the problem?

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