Mobile navigation broken when data-fragment-index skips index 0

[FlippingBinary]

This seems to only affect mobile navigation, even as simulated in Vivaldi on Windows 10. When the data-fragment-index property is set to something higher than 0 and there is no element with a data-fragment-index of 0, the pages won't swipe.

Here is the error that appears in the browser console:

scrollview.js:431 Uncaught TypeError: Cannot set properties of undefined (setting 'range')
    at scrollview.js:431:19
    at Array.forEach (<anonymous>)
    at scrollview.js:430:32
    at Array.forEach (<anonymous>)
    at L.setTriggerRanges (scrollview.js:421:22)
    at L.syncPages (scrollview.js:379:8)
    at L.layout (scrollview.js:257:9)
    at Object.Be [as layout] (reveal.js:1037:15)
    at L.activate (scrollview.js:133:15)
    at Be (reveal.js:1025:47)

The obvious solution is to fix the data-fragment-index assignments in the presentation, but it wasn't obvious that this was the reason why slide navigation broke on mobile. I hope this helps someone else.

[hakimel]

Thanks for the report! Fixed in d5896c9