In light of the recent exploits, I decided to update this instance's security headers. I am in no way affiliated with the following site, but the grade of my instance's security headers can be viewed here: https://securityheaders.com/?q=https%3A%2F%2Fchat.maiion.com&hide=on&followRedirects=on - Feel free to check other Lemmy instances and sites.
Per this post there was nothing in the custom_emoji_keyword and custom_emoji postgresql tables for me to delete. The image is below.
What I did delete in the database were the contents of the activity table older than 2 days. According to the developers, the "activity table...is basically a duplicate of the data in the main tables, and not necessary. It needs to be periodically cleared of data older than maybe 2 weeks or a month". However, the developers "went with deleting activities older than 6 months".
In an effort to reduce server disk usage, I was able to reduce the 3GB activity table to just under 1GB.
Before
After
Lastly, I updated lemmy-ui to v0.18.2-rc.2 which should address the exploits that happened on other Lemmy instances. The release page can be found here: https://github.com/LemmyNet/lemmy-ui/releases/tag/0.18.2-rc.2