Issue

The description field for a Web Link or LTI can only contain one paragraph and only text. Any other HTML (e.g. lists, two paragraphs, etc...) will cause the LTI to cease functioning. 

Solution

Keep the description field code and length as simple as possible.

Example

Good Code

<p>A single paragraph description will work.</p>

Bad Code

<p>A two paragraph description</p>
<p>will not work.</p>