Warning after installing other language packs

Version: master
Platform: all
Browser: all

After installing a language pack such as fr from langpacks.mahara.org.
There is a form at the top for changing the language.

Warning issues:

[WAR] ee (lib/pieforms/pieform.php:1408) Pieform element languageselect_lang wants to add headdata to the page, but it's too late. Build your form before generating the page.
Call stack (most recent first):
log_message("Pieform element languageselect_lang wants to add h...", 8, true, true) at /home/sonn/code/mahara/htdocs/lib/errors.php:109
log_warn("Pieform element languageselect_lang wants to add h...") at /home/sonn/code/mahara/htdocs/lib/pieforms/pieform.php:1408
Pieform->build_element_html(array(size 13)) at /home/sonn/code/mahara/htdocs/lib/pieforms/pieform.php:659
Pieform->build() at /home/sonn/code/mahara/htdocs/lib/pieforms/pieform.php:162
Pieform::process(array(size 5)) at /home/sonn/code/mahara/htdocs/lib/pieforms/pieform.php:71
pieform(array(size 5)) at /home/sonn/code/mahara/htdocs/lib/web.php:3604
language_select_form() at /home/sonn/code/mahara/htdocs/lib/web.php:478
smarty() at /home/sonn/code/mahara/htdocs/index.php:93