Is there any way to "protect" code snippets inserted into pages via the text editor? It seems the editor does not like Google asynchronous code snippets. They paste in fine and work, but then if I go back and edit the page the editor automatically wipes out half the code snippet. Simply opening the editor seems to be all it takes to wipe out the code. Mostly an annoyance but if there is an escape sequence it would make life easier.

Are you pasting into the code box? It's next to quotes, link, etc.  

Yes, pasting code into code box. Save and all is well. Open up again to edit something else, the editor wipes out half the Adsense asynchronous code. Works fine with inline code.

What is the code?

<ins class="adsbygoogle"
     style="display:block; text-align:center;"
     data-ad-layout="in-article"
     data-ad-format="fluid"
     data-ad-client="ca-pub-8297745630182067"
     data-ad-slot="7105470538"></ins>
<script>
     (adsbygoogle = window.adsbygoogle || []).push({});
</script>

<ins class="adsbygoogle"
     style="display:block; text-align:center;"
     data-ad-layout="in-article"
     data-ad-format="fluid"
     data-ad-client="ca-pub-8297745630182067"
     data-ad-slot="7105470538"></ins>
<script>
     (adsbygoogle = window.adsbygoogle || []).push({});
</script>

Testing, will try to edit afterwards.

Seems fine here. You might wish to submit a ticket so we can take a look.