Hello,
thx for reporting, we can reproduce the issue on a RTL page, only if the javascript library chosen.jquery.min.js is loaded.
In your case, the js library chosen.jquery.min.js is loaded by the module mod_seminarman_search, it is required for that module. Till now i can not find out why chosen.jquery.min.js does the weird behaviour on the RTL page, but we can simply prevent chosen.jquery.min.js from affecting the sman booking form by editing the following file in module mod_seminarman_search:
/modules/mod_seminarman_search/tmpl/default.php in Line 23:
change
JHtml::_('formbehavior.chosen', 'select');
to
JHtml::_('formbehavior.chosen', '#filter_sman_tag');
Pls update that line in your module directly for now. We will update the same code line in the next release.
Thx again for the reporting.