I was trying to update my site to Joomla 6. It is requested to deactivate the plugin <behaviour - backward compatibility>.
Afetr doing this the site stopped to work
Compatibility of the template with joomla 6.0.2: is it OK ?
5 replies
Hi,
Thanks for reaching out.
Yes, Gazette v2.0.5 works on Joomla 6. I have tested it on Joomla 6.1.0 with PHP 8.4. However, some of the template's bundled modules still use legacy Joomla classes, so the template needs Joomla's backward compatibility plugin to be active. That is why your site stopped working as soon as you disabled it.
Could you please confirm your exact Joomla version (System > Information > System Information)? The steps below assume Joomla 5.4.x, which is the version required before updating to Joomla 6.
There are two plugins with similar names, and they behave differently:
- Behaviour - Backward Compatibility (the Joomla 5 one): the Joomla 6 pre-update check asks you to disable this.
- Behaviour - Backward Compatibility 6: this must stay enabled, before and after the update. It only becomes active once the site is on Joomla 6.
So while you are still on Joomla 5 with the first plugin disabled, the front end will show an error (Class "JHtml" not found). This is expected and temporary. Once the update to Joomla 6 completes, the "Backward Compatibility 6" plugin takes over and the site works again.
Please follow these steps:
- Take a full backup of your site (files and database).
- Make sure Gazette (2.0.5), Helix Ultimate and SP Page Builder are updated to their latest versions.
- Go to System > Manage > Plugins, search for "Backward", and confirm Behaviour - Backward Compatibility 6 is enabled. This plugin is included from Joomla 5.4 onwards, so if you don't see it, please update to the latest Joomla 5.4.x first.
- Disable Behaviour - Backward Compatibility, then immediately run the Joomla 6 update from System > Update > Joomla.
- After the update, clear the Joomla cache (System > Maintenance > Clear Cache) and check the site. Keep "Behaviour - Backward Compatibility 6" enabled.
If you want your current site back online first, simply re-enable Behaviour - Backward Compatibility from System > Manage > Plugins. If the administrator area is not reachable either, open the #__extensions table in phpMyAdmin (your table prefix replaces #__), find the row with folder behaviour and element compat, and set enabled to 1.
For more background, Joomla's official upgrade guide explains both plugins and the full process: https://guide.joomla.org/user-guide/migration/joomla-5-to-6-planning-and-upgrade-step-by-step
If the issue persists after the update, please share the exact error message along with your administrator access in the Hidden Content box, and we will check it directly.
Best regards
Thank you for your hints.
by the last attempt once I disabled the "Behaviour - Backward Compatibility (the Joomla 5 one)" then also the administrator area stopped to work.
Should I try again ....?
My version are : Joomla 5.4.10 / php 8.5, gazette 2.05 /SP 6.10.0/ Helix 2.2.11
I've tried again and as soon as I disabled the plugi "Behaviour - Backward Compatibility" (the Joomla 5 one) the site (also the administrative part) stopped to work.
See the error message on at this link (https://www.fotoclublugano.com/images/2026/Joomla%20error/Errore%20di%20Joomla.jpg)
Could you help ? Thank you in advance
Hi,
Sorry for your experience.
Let me check it deeply. I will get back to you soon.
Thanks for your patience.