* * The html tag in the message is added to the issue description, and the format remains the same

You will need to code for all the stuff that the converter can not do with your content.

Yes, the standard convertXHtmlToWikiMarkup conversion does not meet, what do I do

Ok, so your code is going to need to read the HTML, parse it for formatting and convert that into markup, and tell Jira that the field is markup. convertXHtmlToWikiMarkup can do the basics, but you will have to parse and interpret the bits it cannot.

nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }