I believe I know what might be causing it, a plugin pulling urls from WP_SITEURL instead of WP_HOME, but what is the code I should be looking for to find the culprit?
I already did
wp search-replace wp-content/uploads app/uploads to fix URLs in the content of pages.
wp/app/uploads turns up no results.
I’ve been able to fix it temporarily by symlinking my apps folder into wp but that won’t work for long
Update, it appears to only happen with the responsive images, srcset ones.