Leaflet Choropleth Map - switch to Leaflet 1.2 - leaflet

Question

I have a problem with my map. I switched to Leaflet 1.2 and one of the functions is not working correctly.
The code is here:
http://mapaszlakow.eu/mapa1.2.html
When activating an overlay which is geojson via js and clicking a bicycle route it zooms in to a route but it is not highlighted and the info window does not show up.
Here is exactly the same example that is working but on the older version of Leaflet (I think it is 0.7).
http://mapaszlakow.eu/
I can't locate the problem, the only thing I did is switching to Leaflet 1.2, I will be greatful for help.
EDIT: I believe, the problem is somewhere here:
function select(layer) {
info.update(layer.feature.properties);
if (selected !== null) {
var previous = selected;
}
map.fitBounds(layer.getBounds());
selected = layer;
if (previous) {
dehighlight(previous);
}
}
var selected = null;

Answer 1

I've tested your code from http://mapaszlakow.eu/mapa1.2.html and it works almost fine - on hover it highlights route correctly, on click it zooms to route extent - except from showing the popup info. To fix this please check out the fiddle I made from your code:
http://jsfiddle.net/5z17y5oL/18/ (this fiddle must be accessed through http because your server doesn't serve data with https)
The main difference is that I passed parameter to info.update(e.feature.properties); occurrences.
EDIT
My edited fiddle is here: http://jsfiddle.net/5z17y5oL/25/
So I moved the info.update(e.feature.properties); to be called from layer click listener. On map clicked layer style is reset and info is clearing as it's receiving null.
.....
onEachFeature: function(feature, layer) {
layer.on({
.....
'click': function(e) {
select(e.target);
info.update(e.feature.properties);
}
});
map.on({
'click': function(e) {
bicyclegeojson.resetStyle(layer);
info.update(null);
selected = null;
}
});
....
//end of EDIT
One more thing - you have small error, you should change this line:
map.addControl(layerControl).addTo(map);
to
map.addControl(layerControl);