Fixing the Divi sidebar ad issue
So I have the ad that you're seeing on the right was causing me a bit of angst. The sidebar wasn't wide enough. A bit of CSS hacking later it's fixed.
.with_sidebar .et_pb_extra_column_main {min-width: 60%;}.et_pb_extra_column_sidebar {width: 340px;min-width: 340px;max-width: 340px;}
Basically, what's going on here is changing the minimum width from the default 75% to something smaller. Then forcing the sidebar from it's default 25% to 340px. Basically the main column still has a 75% preferred width, but will shrink to accommodate. Even though it wants to be 75%, it'll accept being less. I got the 60% based on trial and error with when the page reconfigures to a different layout.