All backend config is the same. All the cache data is deleted (When Install/Uninstall/Enable/Disable Add-on). Why is this necessary?
For example: Xen Cache add-on cache query count thread in forum. Then, you install an another add-on (We'll call it B). This add-on also listen to modify query...
See this config in xenforo core config:
$config['cache']['cacheSessions'] = true;
All cache data is deleted (As flush cache). If xenforo core cache session, this action may be delete all cache session data.
In this version, the add-on support only soft delete post in thread. This add-on was created at the request of @dwi. Discussion: http://xenforo.com/community/threads/notify-user-when-his-post-gets-soft-deleted-hidden-with-corresponding-reason.66626/
No, it does not caching the last post. However, some of the information is stored in the xf_thread tables to offload query (JOIN). So I suggest not to set the option "List Forum Thread" or "List Sticky Forum" is too long for the viewer still feels realtime. With the big board just 5 second cache...