Pull Request for Issue # .

Summary of Changes

In Joomla 5.4 and earlier, language passed via lang variable is always used (takes highest priority) in language filter plugin (see https://github.com/joomla/joomla-cms/blob/5.4-dev/plugins/system/languagefilter/src/Extension/LanguageFilter.php#L412).

In Joomla 6.0, due to the change in this PR #43858, if Remove URL Language Code parameter set to Yes in System - Language Filter plugin, Joomla will use default language if it could not detect language from sef URL, not respect the language passed in lang variable when it is passed. This PR just fixes that wrong (backward incompatible) change.

Testing Instructions

• Uses Joomla 6.0 (any version)
• Setup a multilingual website with two languages (default is English and one additional language like German). You can Sample Data - Multilingual to setup test site faster if needed.
• Go to System -> Plugins, find System - Language Filter plugin, set Remove URL Language Code parameter to Yes
• Access to homepage of your site and appends ?lang=de to URL, for example http://localhost/joomla/index.php?lang=de

Actual result BEFORE applying this Pull Request

• The site in default language (English in this case is displayed). It ignore the language passed in lang variable (when lang is passed, site should be displayed in the passed language - German in this example, same behavior with Joomla 5.4 and earlier)

Expected result AFTER applying this Pull Request

• Site is displayed in the expected language passed via lang variable in URL (German in this example) like in Joomla 5.4 and earlier Joomla version

Link to documentations

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

• No documentation changes for manual.joomla.org needed