Custom Headers with Page Caching

Are there any suggestions on how to get custom headers set in a Controller to work in conjunction with the Kirby page caching system?

If I modify the headers as described here, it’ll work on the first load of the page, but subsequent page requests will use the cached version and bypass the controller completely.

Hm, the header is actually stored in the cache file as well-


even if that’s added in a before-route hook.

So my answer is: no idea how to circumvent that other then deleting the cache.