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.