Today on Watch Me Work I'm doing a two-hop live upgrade of a real Joomla 4 site — Joomla 4 → 5 → 6 — using StageIt to clone the live site into a staging environment first (Rule 0 of any real major upgrade), then running both upgrades on the stage with cs-mcp-for-j (Cybersalt's Joomla → MCP extension) helping drive the work. Once we're on Joomla 6, the interesting part: turning off the backwards-compatibility plugins (plg_behaviour_compat and plg_behaviour_compat6) and seeing what actually breaks. If you've been putting off your Joomla 6 upgrade because you're still on J4 and don't know where to start, or because you're not sure your extensions are ready — this one's for you. Here's what I'll cover live:
✅ Rule 0 — never do a J6 upgrade on live. Clone with StageIt first.
✅ Site tour — a real Cybersalt-managed Joomla 4.4.14 site with a stack of vendor extensions (JCE, JMP File Manager, JoomlaCK family, Regular Labs, ConvertForms, Phoca, Akeeba)
✅ Pre-flight discipline — Akeeba backup, DB snapshot, extension audit, Joomla Update's own pre-update check at each hop
✅ Hop 1: Joomla 4 → Joomla 5 on the stage (admin path, extension-compat panel, what to do with vendor warnings)
✅ Hop 2: Joomla 5 → Joomla 6 on the stage (admin path + the new cs-mcp-for-j Joomla Update tools)
✅ What the J6 backwards-compat plugins actually do — plg_behaviour_compat + plg_behaviour_compat6
✅ Why cs-mcp-for-j REFUSES to disable the BC plugins for you (and why that's the right instinct)
✅ Turning BC off manually via the admin UI — the safe way
✅ Walking the site with BC off — every extension surface, what still works, what fatals
✅ How to recover if you lock yourself out (direct DB, quickly)
✅ Chat Q&A cs-mcp-for-j is free (GPL-2-or-later) and installs on any Joomla 5 or 6 site. Turns your Joomla into its own MCP server so Claude can manage it directly — no local Node/Python install. StageIt is a staging manager for Joomla 4/5/6 — clones your live site into a /stageit/ subdirectory so you can test upgrades before touching production.
🔗 Links mentioned:
- cs-mcp-for-j on GitHub: https://github.com/cybersalt/cs-mcp-f...
- cs-mcp-for-j on Cybersalt: https://www.cybersalt.com/extensions/...
- Joomla 5 upgrade docs: https://docs.joomla.org/J5.x:Upgradin...
- Joomla 6 upgrade docs: https://docs.joomla.org/J6.x:Upgradin...
- Joomla Backwards Compatibility Plugin docs: https://docs.joomla.org/J5.x:Backward...
- Cybersalt Consulting: https://www.cybersalt.com