Is there a way to reset the effect of AP.sizeToParent()?

I use AP.sizeToParent() and AP.resize(“100%”, “100%”) to create a single page app screen for a WYSIWYG editor. (API: )
If I then use a link to navigate back to a “regular”, long, scrollable page in the same iframe, I get double scrollbars, the outer one effectively disabled. The bug disappears after a full Jira page reload.

I investigated that AP.sizeToParent() adds some extra CSS classes to the iframe that I cannot remove from code. I think there must be a way to reset the effect of AP.sizeToParent() from JS but I don’t know how. Does anyone have experience with this problem?