could not find an associate log for electrs.
It looks like the tutorial you followed did not enable the log for both electrs and mempool. Try to add the below configurations:
# Electrs
# /usr/local/etc/electrs/config.toml
# add this on the last line
verbose = 4
---
# mempool-config.json
# https://github.com/seth586/guides/blob/master/FreeNAS/bitcoin/freenas_8_mempool.md
# find "SYSLOG" and then change "ENABLED" to true
"SYSLOG": {
"ENABLED": true,
"HOST": "127.0.0.1",
"PORT": 514,
"MIN_PRIORITY": "info",
"FACILITY": "local7"
},
Then restart both applications. After that, run this on terminal
$ tail -f /var/log/syslog and then try to open up mempool site again and visit any addresses. Look up at the terminal, it will probably show the loggings.