[#46810] - [6.0] Multilingual: Fix language passed via lang variable is ignored
- Fixed in Code Base
- 5 Feb 2026
- Medium
- Build: 6.0-dev
- # 46810
- Diff
- joomdonation:fix_language_is_ignored
User tests: Successful: Unsuccessful:
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:
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Documentation link for docs.joomla.org:
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No documentation changes for docs.joomla.org needed
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Pull Request link for manual.joomla.org:
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No documentation changes for manual.joomla.org needed
| Status | New | ⇒ | Pending |
joomla-cms-bot
- | Category | ⇒ | Front End Plugins |
Thanks @exlemor for testing. No, sub-folder is not effected because that happens on my local Joomla installation, too and I can clearly see the issue by code reading. It is strange that it is working OK on your test site. Just want to be sure, the site is a fresh Joomla 6 installation (because the issue only happens with Joomla 6, it works well on Joomla 5.4 and earlier)
I have tested this item ✅ successfully on 130a29a
This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/46810.
I have tested this item ✅ successfully on 130a29a
Site is displayed correctly in the expected language passed via lang variable in URL, in my case italian language (/index.php?lang=it).
Thanks
This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/46810.
Thanks @exlemor for testing. No, sub-folder is not effected because that happens on my local Joomla installation, too and I can clearly see the issue by code reading. It is strange that it is working OK on your test site. Just want to be sure, the site is a fresh Joomla 6 installation (because the issue only happens with Joomla 6, it works well on Joomla 5.4 and earlier)
Hi @joomdonation, it is a Joomla 6 Nightly Site from the day before, and I just retested and it works without the PR applied. :/
Hi @joomdonation, it is a Joomla 6 Nightly Site from the day before, and I just retested and it works without the PR applied.
That's strange because I can see the issue, both by actual test and code reading :). @Fedik @Hackwar You two worked on the most recent changes for the plugin, would be great if you could do a code review for this PR. Thanks.
Hm, I do not see how this changes may work.
The default lang will be overrided in few line down, when it is correct:
joomla-cms/plugins/system/languagefilter/src/Extension/LanguageFilter.php
Lines 381 to 385 in 25b1369
With your changes for URL with ?lang=foobar the default language will not be set.
I did not tested, just looking the code. Maybe I missed something.
The default
langwill be overrided in few line down, when it is correct:
For a none SEF URL like https://domain.com/index.php?option=com_name&task=do_something&lang=de for example, $sef is empty, so isset($this->sefs[$sef]) return false, so lang is not set in that block
In my specific case, there is AJAX post request made to a none SEF url like above, the wrong language is use and cause wrong behavior.
Okay, then it seems makes sense.
Okay, then it seems makes sense.
Thanks
| Status | Pending | ⇒ | Ready to Commit |
RTC
This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/46810.
| Labels |
Added:
RTC
bug
PR-6.0-dev
|
||
| Status | Ready to Commit | ⇒ | Fixed in Code Base |
| Closed_Date | 0000-00-00 00:00:00 | ⇒ | 2026-02-05 11:10:25 |
| Closed_By | ⇒ | Bodge-IT |
Thanks for the fix @joomdonation and thanks @mariantanase and @ceford for time offered for testing
Thanks to all !
@joomdonation is it because my test website is in a subfolder that
https://www.domain.com/_j6b2n/index.php?lang=fr - shows French version
https://www.domain.com/_j6b2n/index.php?lang=en - shows English version
WITHOUT the PR applied while having the System - Language Filter plugin --> set Remove URL Language Code parameter to Yes or is it because I have the Language Filter settings set this way (beyond the Remove URL Language Code set to Yes I mean)
Thanks for the clarification :)