The composer currently uses a combination of Markdown, bbCode, and HTML.
Don’t feel alone, many have problems with it. (especially when it wants to strip out tags)
Two ways I know of
Select the code block and click the </> icon in the toolbar (indents block 4 spaces each line)
this took care of the rest of it:
<script type="text/javascript">
var runtime2 = <?php echo $runtime; ?>;
document.getElementById("p1").innerHTML = runtime2;
</code>
Or put 3 backticks ```on their own line before and after the code block
this took care of the rest of it:
<script type="text/javascript">
var runtime2 = <?php echo $runtime; ?>;
document.getElementById("p1").innerHTML = runtime2;
</code>
EDIT
Ah, It looks like you figured it out on your own ![]()
* for inline <tags> a single backtick before and after will work