This filename is not safe to use in an URL

Hi Thomas,
in backend, in "administrator/index.php?option=com_sermonspeaker&view=sermons" if you want to filter sermons, it is not possible to choose "Speaker" and "Series" in Search tools even if you have created "Speakers" and "Series". Pls. see attached image.

Is it only my problem? (Tested also with your "com_sermonspeaker-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17.zip" version) and there is same problem.
Thanks
Radovan

Try with this:

Hi,
1 - working in the list of sermons, but not working in detail of sermon (during editing).
There is fatal error:
Fatal error: Call to undefined method JApplicationAdministrator::isClient() in /www/r/-/u28922/public_html/_sub/radiologos2017/administrator/components/com_sermonspeaker/models/fields/speakerlist.php on line 51

2 - there is also problem to choose "speaker" and "series" in sermon detail too (in version "com_sermonspeaker-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17.zip" and this I cannot to check because of fatal error of "com_sermonspeaker-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18.zip"

3- Sermon speker shows me " This filename is not safe to use in an URL" for file named "/audio/rozhovory/roz-2015-anim1--rekl.mp3" - what is wrong? Files was automatically created by link in frontend (tools)

Thanks,
Radovan

Ah, that `isClient()` method is new with Joomla 3.7.0, didn't notice that when I tried it on my testing enviroment which runs on the development version of Joomla.

Please try with the attached version which has those particular lines reverted to the old code.

The filename is likely a "false negative". The warning seems to be triggered by the double "--" you have in the filename.
I'd say you can ignore that message or change the filename to remove on "-" there.

Hi Thomas, thank you, now it seems to be O.K.