Having many SVG DomMarkers in HERE maps causes lag - here-api

Question

I'm using HERE maps 3.0 (also tried 3.1 and have the same issue) with the default layers in an angular project. The map has DomMarkers using a complex SVG icon with many paths inside a div.
I noticed that adding many markers (over 200) causes a lag when zooming or moving around the map.
I'm using SVG instead of static image files to be able to change the colour and modify the shape of the icon before adding it to the map.
Using a dom icon with multiple divs shaped with CSS instead of the SVG, results in the same lag.
If I use a more simple SVG or a simple div, the lag is reduced significantly.
What's causing the lag? Is it caused by the complexity of the SVG, or the large and many paths it has?
Is there a way to have complex SVG markers and eliminate the lag?
My SVG:
<?xml version="1.0" encoding="utf-8"?>
<!-- Generator: Adobe Illustrator 19.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 0) -->
<svg version="1.1" id="Layer_2" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
viewBox="-656 895.2 221.2 259.8" style="enable-background:new -656 895.2 221.2 259.8;" xml:space="preserve">
<g>
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</g>
<g>
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</g>
<g>
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"/>
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<g>
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The markers are added from a for loop to a group (H.map.Group) that was already added in the map. The lag is happening not while loading the markers, but when trying to move around the map or zoom in and out. It's very laggy especially when zoomed out and many markers are visible.
adding the group in the map:
this.map.addObject(this.markerGroup);
adding a marker:
addMarker(data) {
const id = data.id;
if (!mapObjects[id]) {
let coords;
coords = { lat: data.lat, lng: data.lon };
const icon = new H.map.DomIcon(this.createMarkerIcon(data));
this.mapObjects[id] = new H.map.DomMarker(coords, { icon: icon });
this.mapObjects[id].setData(data);
this.markerGroup.addObject(this.mapObjects[id]);
} else if (this.markerChanged(data)) {
this.updateMarker(data);
}
}
loop that adds the markers:
markers.forEach(markerData => {
this.addMarker(markerData);
});
edit: svg added, snippets added

Answer 1

Caching could help you to avoid this zoom out lag. reading larger marker data again and again with complex svg making it laggy. you can try to store the markers in one variable and cache it if the data is not changing all the time, like below
var testObject = { 'one': 1, 'two': 2, 'three': 3 };
// Put the object into storage
localStorage.setItem('testObject', JSON.stringify(testObject));
// Retrieve the object from storage
var retrievedObject = localStorage.getItem('testObject');

Answer 2

The problem was that I used H.map.DomMarker instead of H.map.Marker and the many html elements caused the map to lag.
H.map.Markers are rendered on the map and don't cause zooming and moving lag.