Certain files updating *every half minute*

I recently set up a new server set up with Nextcloud. I have my main boot drive, where the Nextcloud files are stored, and then I have my data drive, where Nextcloud stores all my personal files.
Everything works fine, but, I noticed both drives keep writing every 30 seconds whenever I’m logged in through a web browser. Everything goes silent when I log out. I don’t have to be doing anything at all. It doesn’t even have to be the active tab, it just keep writing and I don’t know why.
On the data drive, there’s only one file being written to: …/cache/music_collection.json
On the boot drive, there are several files:
/var/lib/php/sessions/sess_thdf8p… (not sure if the full filename is incriminating or not)

According to the apache access log, it basically seems like the page is re-loading every 30 seconds. The files starting with “ib” seem to get big pretty quickly. I also noticed sometimes /var/lib/mysql/nextclouddb/oc_authtoken.ibd shows up, but I enabled 2FA which seemed to weed that out.

I haven’t confirmed if [all of] these files are changing in size, I just know the system is constantly modifying them. Any reason for this, or how to stop it? I like keeping the tab open for easy access, but that seems like an easy way to kill SSD lifespan.