This bug is still present, if you set the initial value to 0, neither setting the slider to middle or start value will work.

Strange is that if you save survey and resume it later the 0 value is taken into account.

@markusfluer, this one is causing quite some issues. It is the issue we discussed on Skype recently: "Ich glaube ich weiß woran es liegt, da die mitte den Wert '0' hat wird das falsch interpretiert, das liegt a der php version".
Please have another look if possible.

I can confirm that setting the initial value at 0 results in showing the initial position to be at 5 (scale 0 - 100)

slider2.png (64,094 bytes)   

slider2.png (64,094 bytes)   

slider1.png (43,256 bytes)   

slider1.png (43,256 bytes)   

Here sample survey

I think all is fixed now
https://bugs.limesurvey.org/view.php?id=14618
https://bugs.limesurvey.org/view.php?id=14016

@tammo : on 479531 : you have the 2 settings : middle position + slider start at.
<s>Strangely : middle position is set at end … then it get the priority. I add a information about that in help text.</s>
I didn't update it, because it broke existing survey.

Capture d’écran du 2019-03-11 08-18-54.png (3,230 bytes)   

Capture d’écran du 2019-03-11 08-18-54.png (3,230 bytes)   

OK, think i fixed whole, please review

https://github.com/LimeSurvey/LimeSurvey/commit/97750a52dbf22fd858ba62213ba6938de6460e81

Did every release since Feb 2018 had this "major" issue? Or is this issue a reoccurring one?

@jelo : personnaly : i don't know …

The value "Slider initial value set at start: 0 " seem to be kept in the system, even when you remove the value and save the options again. The overview still shows the value set.

Sidenote: The slider question should be a separate questiontype. Will ease debugging and helps to build a coherent set of options for a question type. Questions like Gender and Yes/No are separate question types, but a slider is inside a Multiple numerical input.

About SideNote : must be moved to Question Theme i thin, since data saved is exactly the same than multiple numeric.

The value "Slider initial value set at start: 0 " seem to be kept in the system, even when you remove the value and save the options again. The overview still shows the value set.

Slider initial value set at start: 0 mean it's OFF
Default is 1 , then when it‘s ON : nothing is shown.

Since Question edit was rewritten (with another maybe biggest issue) : no need to work on it.

Fixed in version 3.17.3