WebGL powers the interactive map. If it is turned off, here is how
to switch it back on.
Update your graphics drivers and make sure hardware acceleration is not blocked. Some systems disable WebGL on older GPUs.
Other browsers
Open about:config, search for webgl.disabled and set it to false. On LibreWolf you may also need webgl.force-enabled set to true.
In Settings turn on “Use graphics acceleration when available”, then restart. Open chrome://gpu to confirm WebGL is enabled.
Open Settings → Advanced and enable the Develop menu, then choose Develop and turn on WebGL.