Conditional Formatting not working on html code

Hi, I tried applying conditional formatting to a list of cells with html, and the formatting I get is completely out of whack. Instead of highlighting duplicate values, all cells that start with an opening tag <li> are highlighted (even if they're unique), and all cells that start with a closing tag </li> aren't highlighted (even if they occur more than once). COUNTIF is also acting weird--when I search for the value in B2, it returns the number of cells with the < character, and it returns 0 for values that start with </.

It looks like Excel is automatically performing an action based on the < and </ characters, but I've been digging through forums and search results and can't find any mention of Excel treating these characters differently. Changing the cell format to Text or adding an apostrophe doesn't do anything. I've been using Highlight Duplicates for years and haven't found any characters that behave like this. I need to include exact html tags in my final document, so taking them out would add unnecessary steps.

This worked, thank you! Do you happen to know why excel doesn't work on the < character?