@scott.dudley @AndreasEbert Thank you so much for helping me out! We had in fact already migrated everything to Java config but hadn’t made this app transformerless yet (we’ve had lots of issues with the update, so I end up getting confused with all the different problems).
After I added Atlassian-Plugin-Key I first ran into a Atlassian Cache crashes Confluence… first. After I applied the workaround with @Bean(destroyMethod="") to cacheManager() in my config file things started to work. Anyone knows if there has been any update to this? Seems we’re still supposed to use CacheManager rather than CacheFactory?
Anyway, I consider my problem solved, thanks again!!