Please help us help you and fill where relevant:
Your LimeSurvey version: 3.x (but portable to 5.x)
Own server
Survey theme/template: bootstrap
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Hello there, is it possible to write a new plugin who provide a custom location mapservice with a complete rewrite of the short text question type?
My goal is to have a Leaflet representation using custom tile map services and custom layer added to the map. Also marker style is needed.

Is there any inspiration around?

github.com/LimeSurvey/LimeSurvey/pull/218

I found the first implementation of this feature. Looks like is hacked into code. No space for mapservice plugins.

Maybe can be overriden with a massive huge javascript text-display question filling up a equation-question?

Sample : gitlab.com/SondagesPro/QuestionTheme/MapIgn

Usage of leaflet with other parameters and settings

Thanks Denis, I'll study your code in the near future, now we rushed for a super custom question-type-label with an amount of javascript inside