Critical — prevents system from working

Remote Pollers (How-To-Setup-Remote-Pollers.md)

• Unclosed PHP string literal: `$rdatabase_hostname = '192.168.1.5;` — missing closing quote causes PHP parse error; remote poller silently fails to connect
• `GRANT ALL PRIVILEGES ... IDENTIFIED BY` syntax removed in MySQL 8.0 and MariaDB 10.5.2; produces `ERROR 1064` on any modern stack; must be split into `CREATE USER` + `GRANT`

Ubuntu/Debian install guide (Installing-Under-Ubuntu-Debian.md)

• Cron job runs as `apache` user, which does not exist on Ubuntu/Debian (correct user is `www-data`); poller never runs

Spine build (Spine.md)

• `libmysql++-dev` is the C++ MySQL binding, not what Spine's C code needs; correct package is `default-libmysqlclient-dev`
• `librrds-perl` is RRD Perl bindings, not a Spine build dependency; correct package is `librrd-dev`
• `wget ` angle bracket syntax causes silent shell failure (shell interprets `<` as stdin redirect)
• `cactid.php` referenced as a file that doesn't exist; the poller is `poller.php` for both cron and systemd

High — incorrect behavior

Upgrading-Cacti.md

• `chown -R apache:apache rra/ log/` wrong on Ubuntu/Debian (most common platform); should note `www-data` as the correct user

Medium — misleads contributors

Standards-Code-Formatting.md

• Vim config block includes `set expandtab` (converts tabs to spaces) directly contradicting the paragraph that says "always use tabs to indent"; should be `set noexpandtab`

Low

Plugin-Development.md

• `it's functionality` → `its functionality`
• `Squirrel Mail` → `SquirrelMail` (one word, camelcase)
• `http://www.chartjs.org/\` → `https://www.chartjs.org/\` (Chart.js moved to HTTPS)
• `http://omnipotent.net/jquery.sparkline/\` appears dead; consider removing or replacing