does not load well without the inspector

Can you explain a bit more about where you see this problem? What sort of machine are you using? Which operating system is it using? Which web browser? Which version?

When I load the map it doesn't center it inside the div, just an image appears. Then I open the inspector and load the other images and center the map inside the div. I use an Ubuntu 20 operating system, and I see the map from the Mozilla Firefox 1.0 browser. Thanks for your reply.

Just to confirm - you're just browsing to "https://www.openstreetmap.org" , you're not trying to do anything "clever" like trying to embed https://www.openstreetmap.org as part of a different website?

There is no "Ubuntu 20", but presumably your are using "Ubuntu 20.04" or "Ubuntu 20.10".

Are you really using verion 1.0 of Firefox? This seems unlikely.

Ok I think I have not explained myself well. I am using Leaflet and I access openstreetmap. This is the code: var map = L.map ( "map", { center: [markers [0] [1], markers [0] [2]], zoom: 10, zoomControl: true, preferCanvas: false, } );

var tile_layer = L.tileLayer ( "https: // {s} .tile.openstreetmap.org / {z} / {x} / {y} .png", {"attribution": "Data by \ u0026copy; \ u003ca href = \" http: //openstreetmap.org \ "\ u003eOpenStreetMap \ u003c / a \ u003e, under \ u003ca href = \" http: //www.openstreetmap. org / copyright \ "\ u003eODbL \ u003c / a \ u003e.", "detectRetina": false, "maxNativeZoom": 18, "maxZoom": 18, "minZoom": 0, "noWrap": false, "opacity": 1, "subdomains": "abc", "tms": false} ) .addTo (mapper);

And I think the problem is in openstreetmap.org.

If you want to compare your code with some that works have a look at https://github.com/SomeoneElseOSM/mod_tile/blob/switch2osm/extra/sample_leaflet.html .