Hi MiKa!
Right, it is like this.
– I use Gutenberg
– The existing posts with problems where created with Gutenberg
– No cache plugins
– When I create a test post, publish and reopen it, everything is fine – the map is shown.
For this test, if have played around a little:
Apparently the problem only occurs with post, which already have some OSM shortcodes in the text. Old posts without shortcodes will show the map.
Regards,
Andreas