@zero-24 #34599

@jschmi102 please provide your update xml

And please provide the following:

• Joomla Version in which you run the pre upgrade checker
• Joomla Update Server Configuration

Thanks

Hi,

Isssue #34599 describes and discusses most of the problems of this issue.

Joomla V3.10 and Joomla V4 have implemented a checking mechanism to provide a consistent compatibility information for joomla extensions e.g. to be used for a migration to Joomla V4. This information is based on the setting of an update server (stored in xml format). This setting will have to be done by the developer of extensions. This also means that the developer must provide a valid compatibility information, so that a user can rely on this info and process his/her migration effort successfully. E,g. Developer should not “lie” or mistakenly define a compatibility where is none (I saw a couple of extensions where the developer defined a genereic version for updates version=".*" - which results in a compatibility for any joomla version, which is certainly wrong).
On the other hand, Joomla should provide a consistent compatibility information – this means Info from joomla 3.10 should be similar to Joomla 4.x Unfortunately this is not the case with Joomla 4.0 RC3 and Joomla 3.10. alapha 8. Whereas Joomla 3.10 reports “No Update Required” (which is correct) does Joomla 4.0RC3 also tell “No Update Required” but warns the user additionally better not to install the extension, though the developer has defined a complete compatibility for Joomla4.
I'm using an update server for my extension to support updates on Joomla V3.9, V3.10 and V4.0.
(click http://www.jschmidt-systemberatung.de/downloads/jmootips12_updates.xml to see contents):

<updateservers>
 <server type="extension" priority="1" name="jmootips1.2 Updates">http://www.jschmidt-systemberatung.de/downloads/jmootips12_updates.xml
 </server>
</updateservers>  

It seems that only for system type plugins warn ing message “Package Potentially Serious Problem.” will be issued on Joomla 4 RC3.

It seems that only for system type plugins warn ing message “Package Potentially Serious Problem.” will be issued on Joomla 4 RC3.

Yes thats correct as they could result in the site being down

Yes thats correct as they could result in the site being down

Any other type of plugins could cause a system crash (e.g. a content plugin) - so for me this argument is not understandable

No thats not correct

E.g. a content plugin will be trigered by onContentPrepare event - this means practically on each page. If there is a serious bug it will crash the system.

it will crash the site but you can still access it in order to disable the plugin. with an errant system plugin it will kill the site and you will need to have database access to repair it

The issue has been explained here and the string has been updated here: #34771